Boat electrical system

I didn't want to hijack any of JLH's threads.  I am looking to run some new electrical in my boat as well, but a little different in components.  Let me know if there is something else to think of.
 
First a little brief of what I have.  2 gas motors, one has electric start with battery charge, the other is pull start.  So, I am assuming this is all that is on the starter battery, although there seems to be a few more wires? 
 
For the trolling battery, I have a bow mounted trolling motor (12 V - think 43lb), running lights, marine radio, depth finder, bilge pump, live well pump, electrical hook ups for 2 downriggers and 2 interior night fishing lights.  I would also like to add an aerator.
 
My first objective is to replace the trolling motor wiring, since it is being interupted somewhere under my decking.  I am going to add a 50 amp circuit breaker to this line as well. 
 
I am also looking to try to junction some of wires together, so there aren't 5-6 wires that I need to pull on and off of the terminals every time I take the batteries off to charge.  Is a marine breaker panel a good idea for this?  My plan would be to connect the components to the panel's component side.  On the battery side of the panel, have one source positive and nuetral go to the battery.  Would I need a buss bar /terminal block for this part, or just crimping all of the wires to a "leader" wire be sufficient? 
 
I know a switch is a good idea, since much of the electronics have a phantom power draw.  I would imagine the breaker panel could be used for this as well as surge protection.
 
Is there any need for a breaker on the starting battery?  
 
Does it look like I'm on the right track?  Anything that I'm missing, while I have the wire strippers handy?
 
Thanks,
PT 
 

I rewired both of mine.  Sounds like you are on the right track.  The best advice I had was spend 5 times as much time planning as you do wiring and you will be fine.....