"once again side-engine coding, and 2, I don't have money to get past the 20 connection limit"

Working with API's is fairly straight forward, and something you're going to have to learn if you want to use Away3D, Papervision, Box2D etc.
All you're doing is importing classes and calling methods and getters / setters. It's no different to how you code with Flash anyway.
As for the second point, get the game working first then worry about that.

Maybe check out http://www.nonoba.com/ for a pre-made system with hosting.

"I want to do it in a way where it is pretty much as simple as the method I'm using of just sending and receiving and have no limits to the amount of connections I can have to the server..."

Yeah, I want lots of nice things too.
Writing a MP game is difficult and time consuming, that's why there aren't many out there, it's not due to developers lack of ambition.

Let's say you stick with your way, how does it handle latency for example ? What if one player has a low spec. PC and another has a top of the range one ? How do you plan to sync them up ?

Commercial MP servers cost money for a reason, a hell of a lot of time and effort goes into both making them and stress testing them.

Squize.