So I made a post about my theories story wise. Buy I also wanted to comment on monsters that may be returning. I started the momster hunter with tri and it may influence me a lot so sorry for that lol.

Personally Lagicrus is my all time favorite and only monster I "NEED" everything last this would be cool

Insects and snakes. All of them. The seltas combo, the mmo scorpions the spiders. I dont remember the snakes but I remember fighting them in gen 4? I think.

More aquatic monsters. Not the piscine wyverns. Like leviathans, lagi gobul. They are the only ones I can think of for levithans and would be a great addition. Make them work like the diablos diving into the sand you don't get the 3d water combat but something is better than nothing imo.

If this is the new world is would make sense to see new variants that are more commonplace. Instead of the diablos the monoblos is more prominent in the new world location. Or maybe instead of the usual raptors we have a new one that's more suited for endurance pursuit. This area seems massive and prey pursuit could happen a lot.

I think more "mammal beasts" would be great. Probably classified as brute wyverns or something but we don't see a lot of large mammal monsters, mostly reptile like things.

That's all for my monster ideas. Any comments or other theories are always welcomed.