I have about 33 current tentative world heritage sites I have visited. I know many of you have visited over 100! I thought it might be interesting to share our own personal favorites that we believe are deserving of world heritage status. Try to include a link to your pictures in order to highlight some really worthwhile future candidates. Perhaps this can lead to a Top Missing discussion, since its been awhile?

My Ten (not ranked, alphabetical)
Rade de Marseille (France)
Lake Titicaca (Peru)
El Nido-Taytay Protected Area (Philippines)
Southwest Alentejo and Costa Vicentina (Portugal)
Getbol, Korea Tidal Flat (Republic of Korea)
California Current Conservation Complex (USA)
Central Park (USA)
Early Chicago Skyscrapers (USA)
Petrified Forest National Park (USA)
White Sands National Park (USA)

Good idea! I have only few TWHS visited yet (25), but I would choose those ten:

Ancient City of Kaunos (Turkey)
Central Park (USA)
Church of Santa Prisca and its Surroundings (Mexico)
Classical Karst (in Slovene language: Klasicni kras) (Slovenia)
Jewish Cemetery in Sarajevo (Bosnia)
Kekova (Turkey)
Kornati National Park and Telašćica Nature Park (Croatia)
Region Lacan-Tún - Usumacinta (Mexico)
Sarajevo - unique symbol of universal multiculture - continual open city (Bosnia)
The timeless, humanistic architecture of Jože Plečnik (Slovenia)

Off the top of my head these are still "wow" to me and not WHS and not even upcoming nominations:

Minoan Palatial Centres
The Cuenca Mirador
Raja Ampat Islands
Orvieto
Temples, Shrines and other structures of Ancient Kamakura
Las Pozas, Xilitla
Welwitschia Plains
El Nido-Taytay Managed Resource Protected Area
Stone Buddhas and Pagodas at Hwasun Unjusa Temple
Levadas of Madeira Island
White Sands National Monument (=>NP)
The President Coolidge
+ruins around the Agean Sea can't remember the best sites

I like this challenge, winterkjm! I've been to only 58 Tentative World Heritage Sites, so that should have made it easy to edit down to ten. Still, I had to leave a couple behind that I still wouldn't mind seeing make the list in the future. Here's my top ten, in no particular order:

Auckland Volcanic Fields (New Zealand)
Padova Urbs Picta (Italy)
Jerash Archaeological Site (Jordan)
The Cultural Landscape of the Benedictine Settlements in Medieval Italy (Italy)
White Sands National Park (USA)
Minoan Palatial Centres (Greece)
Early Chicago Skyscrapers (USA)
Pharaonic Temples in Upper Egypt (Egypt)
The Royal Sites of Ireland (Ireland)
California Current Conservation Complex (USA)

Just missing the cut were:
Qumran: Caves and Monasteries of the Dead Sea Scrolls (Palestine)
Slate Industry of North Wales (UK)

Of my current 41 visited TWHS I would highlight top five, the two of which are more or less doubles:
- Jerash Archaeological City (Ancient Meeting Place of East and West)
- The Historical-Cultural Axis of Fin, Sialk, Kashan OR The Persian House in Central plateau of Iran
- Cultural Landscape of Canyon in Kamenets-Podilsk
- Bagçesaray Palace of the Crimean Khans OR The historical surroundings of Crimean Khans' capital in Bakhchysarai
- Nasqsh-e Rostam and Naqsh-e Rajab

For me the following TWHS I visited merit a WHS status:

Zagori (Greece)
ShUM (Germany)
Mathildenhöhe (Germany)
Spa towns
Beth Shean (Israel)
Synagogues of the Galilee (Israel)
Padua (Italy)
Rouen (France)
Madrid (Spain)
Monastic sites (Ireland)

My Ten (not ranked, alphabetical)

Cathédrale de Saint-Denis (France)
Chapultepec Woods, Hill and Castle (Mexico)
Desert Castles of Ancient Khorezm (Uzbekistan)
Eglises byzantines et post-byzantines de Curtea de Arges (Romania)
Historical city of Izamal (Izamal, Mayan continuity in an Historical City) (Mexico)
Historical Lisbon, Global City (Portugal)
Inle Lake (Myanmar)
Jerash Archaeological City (Ancient Meeting Place of East and West) (Jordan)
Rouen : ensemble urbain à pans de bois, cathédrale, église Saint-Ouen, église Saint Maclou (France)
The town of Melnik and the Rozhen Monastery (Bulgaria)

Took me a while to choose; there are many more I'd like to see inscribed...
Lake Titicaca (2005), Bolivia, Peru
Archaeological Sites of the Ancient Shu State: Site at Jinsha and Joint Tombs of Boat- shaped Coffins in Chengdu City, Sichuan Province; Site of Sanxingdui in Guanghan City, Sichuan Province 29C.BC-5C.BC (2013), China
The Qutb Shahi Monuments of Hyderabad Golconda Fort, Qutb Shahi Tombs, Charminar (2010), India
Jerash Archaeological City (Ancient Meeting Place of East and West) (2004), Jordan
Ring of cenotes of Chicxulub Crater, Yucatan (2012), Mexico
Ouballang ra Ngebedech (Ngebedech Terraces) (2004), Palau
Mardin Cultural Landscape (2000), Turkey
Cultural Landscape of Canyon in Kamenets-Podilsk (1989), Ukraine
Slate Industry of North Wales (2012), UK
The Historic City of Thula (2002), Yemen

Loving this Top TWHS Challenge! I have only been to 23 TWHS, so I could only pick 5:

1. El Nido-Taytay Managed Resource Protected Area (Philippines)
2. Etosha Pan (Namibia)
3. Shwedagon Pagoda on Singuttara Hill (Myanmar)
4. Nashq-e Rostam and Nashq-e-Rajab (Iran)
5. Chocolate Hills Natural Monument (Philippines)

I also visited these TWHS, and I struggled whether they were in my "most deserving" category or not. All three are wonderful places to explore, undoubtedly. It would be fantastic to one day see them all inscribed, in particular if management is determined satisfactory by ICOMOS, boundaries are logical, protection is high, and there is a cohesive argument for OUV.

I have visited 173 TWHS, my top 10 would include:
- Ancient cities of Upper Myanmar : Innwa, Amarapura, Sagaing, Mingun, Mandalay (T)
- Archaeological Sites of the Ancient Shu State: Site at Jinsha and Joint Tombs of Boat- shaped Coffins in Chengdu City, S (T)
- Benguela Current Marine Ecosystem Sites (T)
- Chor-Bakr (T)
- Dzongs: the centre of temporal and religious authorities (Punakha Dzong, Wangdue Phodrang Dzong, Paro Dzong, Trongsa Dzong and Dagana Dzong) (T)
- Minoan Palatial Centres (Knossos, Phaistos, Malia, Zakros, Kydonia) (T)
- Old Dongola (T)
- Pharaonic temples in Upper Egypt from the Ptolemaic and Roman periods (T)
- Ram Janaki Temple (T)
- Sarajevo - unique symbol of universal multiculture - continual open city (T)

Leaving out the obvious or upcoming ones like Padua.

I'm coming back from Ethiopia, and I finally substitute Inle Lake (Myanmar) with Sacred Landscapes of Tigray (Ethiopia).

Interesting exercise. I've been to over 100 so narrowing it down to 10 (which admittedly could change from day to day) reminded me that there are definitely some high quality sites still out there. I see some group consensus here with a few repeats. I support an update to the Top 50 Missing!
- Dzongs: the centre of temporal and religious authorities (Bhutan)
- Sacred Titicaca Lake (Peru/Bolivia)
- Vardzia-Khertvisi (Georgia)
- Pharaonic temples in Upper Egypt from the Ptolemaic and Roman periods (Egypt)
- Sacred Ensembles of the Hoysala (India)
- Jerash Archaeological City (Jordan)
- Chachapoyas sites of the Utcubamba Valley (Peru)
- White Sands National Monument (USA)
- Sri Harimandir Sahib, Amritsar, Punjab (India)
- Cretaceous Dinosaur Fossil Sites in the Mongolian Gobi (Mongolia)

I have only visited 4 TWHS, so (although I have an already formed opinion on TL sites that deserve to be inscribed, many of them already mentioned by you all) I'll limit my choice to
-"Corcovado National Park and Isla del Caño Biological Reserve"
As per my review, I would prefer a nomination that includes some other protected areas from the Osa Conservation Area (like Peñas Blancas NP and Térraba-Sierpe National Wetland), and the marine area. That of course would require a new TL entry.

To update the Top 50 missing, we could perhaps each offer our 50 favorites from the TL and 50 other favorites that do not appear in the TL.