upgrading all the electronics, need input

[camopaint0707]

So this is my idea for upgrading the electronics in my car. The stereo is a mild setup and I'm just wondering if this idea would work.
I want to run my starting battery in parallel with another battery. Then run an optima deep cycle off of an isolater. Then I'll have a high output alternator which requires a heavy gauge fused wire to run from the alternator to the main battery. Would that work? Hopefully my attachment of my diagram worked.