Ahh, the reasons I always recommend an experienced captain to build with.
That being said, You are doing good as a new builder with your first ship. There will alway be changes made as you go forward. The titans are a bit much and are energy hogs. Use heavy wire and batteries must be able to output a lot.
I would relocate some things but I am a fan of mounting the guns and seeing what room is left. Pump could go behind the motors if you move the back battery. I mounted my Arizona pump mid ship between the batteries so there is another idea.
The waterproof box will probably be problematic seeing as it has so many holes through it so plan for that. I don't use them for that reason.
Push the hoses on further when you are on final assembly and glue them with a dab of CA. You won't be sorry.
The instep needs to be penetrable until you hit 1/2 inch in.
Wait on worrying about water channelling, you have a ways to go before that. Keep it in mind but there will be changes before that.