Dedicated Electrical

Excellent choice.

Same box is fine.

Question is which bar. There are two to chose from.

Use the one with the least major appliances-a/c, etc.

Then look at the ground and try to improve it. 

Buy some Furatech, Pangea or better receptacles.

I ran two 20 amp dedicated lines on 12/2. Seems fine.

Spent $300 on the whole deal.

Thanks guys!

Well, depends on the distance and circuits. If it's a long run and you are planning multiple circuits a sub panel is the way to go.  The voltage drop / foot will be smaller.

A subpanel won't add anyting.  It is often used if you are putting in service to many circuits a long distance from the box. run one big wire and split it up.  or if you are running out of breaker positions in your box.  Neither applies to you.  Jerry