- Didn't find temperature control sensor, which could be useful, in case of fire. Anyway, flood control is presented, so, why not?

- More weapons. We need more handguns, or automated rifles, or something like this

- Bulkheads and all these inner frames, that affected by water pressure, in case of heavy flooding. Seems to be cool feature

- Full-scale crew-vs-crew sub-wars, with suitable arenas, when one\two\or more subs faced against others. Or i just missed something in game?

...to be continued

Temperature control could be cool (Reactor has a temp out remember), but I assume you could get around this by using a water detector and and oxygen detector, where no oxygen AND no water means fire.

More weapons, I guess that's your opinion, there's a mod that adds some russian ones.

Bulkheads again, could be cool, except they wouldn't really work with the current way subs work, as the only time pressure really comes into existance is in the abyss, and doors can be tripped with water detectors.

PVP may be coming, I think Regalis was considering it at one point and the current respawn system is part of a test for it

A smoke or fire detector would be useful. I've noticed in the minimap that even if a room is filled with water, it will still contain oxygen so the water + oxygen detector combo might not work.

More weapons would be cool. It's why I modded my own into the game.

You might be able to build bulkheads already. Just make an outer wall with room in them and separate them with walls, you could connect them to a bilge room so the pump there keep the flooded areas from building up pressure or you could put a pump + water detector in each or the rooms in the Bulkheads so the sensor turn them on and off when water is detected.

PvP sounds awesome. Sadly, my lappy lags like hell so I will probably just keep playing single player.

Let me explain a bit, what i actually meant, when i told about bulkheads and pressure, and so on. Let's imagine, that water comes inside, and filled up entire section - except neighbours, separated by doors/bulkheads/etc. In such circumstances, water can and will pressure these obstacles - and might destroy them completely, slowly decreasing their `hit points` to zero