Started my 18x16 deck. Have a few questions

[Lph008]

Building my 18x16 deck for 24ft pool. 2x10 beams with 2x8 joists. 4x4 posts. Just finished all the 42" deep post holes, this weekend I'll be starting the framing ( I'm working alone so it's going to take a bit).
I personally wanted my deck boards to be over the top of the rails but I will need to put a winter cover on and also for future liner changes. So I figured I would go level with the rail which would solve both these issues but the top rails and post caps aren't your typical straight rails and caps. Theres alot of curves so cutting might be a pain in the but. I also might use composite decking and a wrong cut could be a $50 mistake
Anyone have a deck/pool rail like this?

 

[Lph008]

 

[Pv2]

how much of the pool circumference is going to be surrounded by deck? you don't need much clearance for a cover, seems like deck over top would be easier to deal with. do the designers of these things ever think of stuff like this?

 

[Chasarms]

I slide my decking under the rails. I thought It was a cleaner look and was concerned that continuously splashing the end grain with water would accelerate rot.

 

[Lph008]

I like the look going under the rail but I'm worried about someone stepping on the rail or using the rail to get out of pool. Going over the rail would be the easiest but then you cant remove the rails for liner change. I could always use sand bags over the deck for winter cover but