Custom ROV Help

So, one day I was listening to someone talk, like normally I do with A.D.D. than the idea popped up into my head of making a little "vehicle" or sub to mount a series of GoPros or FPV cameras (which probably won't work as the signal will be horrible due to water.)

I want to do a cheap, little DIY type device, that I can mount a series of GoPros with lighting and a possible power source. Than I would raise and lower it on my kayak. But, every design I "created", I can't achieve a straight line. There is a wobble or drag of some sort. I am no engineer but have others done something like this? Or idea on something regarding mounting underwater GoPros.

Here in northern minnesota, we have some mining pits that they fill up and they go hundreds of feet. One that I grew up cliff jumping at, I just threw the GoPro on a leader and threw it out there and God, it was beautiful. It's another world down there. Scary.

If this doesn't make sense to you, no worries. I have issues transferring what is in my brain to other people in ways they can understand.