Some months ago during a reddit AMA, Izzy told me that it would be very likely to see the summoned thieves from Thieves Guild being used underwater.
They still aren’t usable underwater, but I think they might end up implementing it (in this particular case it shoudn’t be so hard as you can summon other minions underwater, they will only need to change D/D and P/P thieves for Speargun and Harpoon thieves, and probably adjust IA to underwater combat).
And I wonder if there is some plan to make every skill usable underwater. I don’t remember well, but I think during early stages I read (and see) some utility skills changing into a different one when they first presented underwater combat. Maybe I’m wrong but I think it worked that way.
With ground target skills it’s always possible to make an alternative to the skill usable underwater (like creating a “trap sphere” around the caster, or just something different but with the same “feel” or theme).
With some professions it really hurts your favourite playstyle (specially if you associate your specific build to your character “bio”, a Thief Lord in my case as I use TG and Ambush Trap) when you need to change 80% of your heal/utilities/elite skills, and it also limits some professions a lot underwater. Human Thief can only use one Elite Skill when going underwater.
I think it would be great if every utility/heal/elite could be used at some point in the future underwater, or have an alternate functionality so it’s adapted to underwater combat style.
I know it isn’t that big of a deal, but some important content on this game happens underwater and I would like to maintain my favourite build when doing it