Is there going to be a continent restricted conquest or will continent vs continent be allowed as well ?
I would say yes, you could attack other continents. You could go to another continent and set up an inhibitor in order to reduce their territory for whatever reason you deem fit. Most likely, though, we'll add some sort of restriction or increase difficulty; we need to talk about this one.
Will there eventually be a shortage of non-renewable resources, like diamonds ?
Almost certainly. We will be adding at least one Resource Island that will most likely be contentious. The island will, over time, regenerate its resources so people can have a place to go to for farming ores.
What purpose do tgens serve now, besides resource generation ?
Capital is currently, basically, awarded to whatever Alliance has the
most active Territory Generators. TGens
do protect their land (in that you can break a block in enemy territory, but it does not drop the block and regenerates after some time) right now, but since biomes are everywhere, nobody's really protecting much of anything.
Will it be possible to have a part of the town be located in an ocean ?
Towns founded in the Oceans cannot participate in Conquest or Capital Voting and may be forbidden from being in an Alliance (you could have an ocean alliance i guess, though). You'll be warned about this ahead of time (when you try to make a generator). You can have part of your town in the ocean, but the
generator will need to be placed properly in a continent biome (so, not beach, not ocean, basically).
Will there be anything pre-built ? (like towns or dungeons)
Upon launch of the new world, most likely only spawn town will be built; everything else will be fresh. Over time, however, as we add PvE content, we'll warp in dungeons and structures (we'll bring back some of the best builds in Loka's past for PvE stuff possibly

)
Will prowess be transferred ?
Because we are actually
between PvP seasons right now, a Prowess reset is overdue, so no, it will be wiped.
Overall, to me it seems like the map is going to be too small
The plan is to add new islands and continents over time once we run out of room with our current world.
the server will be a bit too PVP oriented
Loka has always (meant to) be more PvP oriented than anything, if you remember. Survive or Die!
Builders will have to be in a constant fear of potentially losing everything they've gathered up
Builders will still likely have protection. Any sieging or town control will not result in block destruction. Like it has been for some time, builds are always protected both by the plugin and by griefing rules. Additionally, a town can choose
not to participate in Conquest and stay peaceful. Whether this keeps you from being annexed or not is something we haven't decided yet.
pre-built stuff - it's going to eventually be raided by more adventurous players, leaving no reward for new explorers
We always block-protect structures that are used for any sort of Lore content. There are other types of structures that may appear and can be consumed and destroyed by players, but that kind of content will likely pop up around the world.
Hopefully this helps!