Welcome to the site, Jimi!
I hope you stick around and participate here in the NJ forum, I tihink you'll find the folks here fairly tolerable...
Well, looks like you've got a pretty nice collection going. So, thinking of an AR carbine... You certainly can't go wrong with either a Bushmaster or Rock River. You can get chrome lined RRs, and all 'non-match' Bushmasters are chrome lined.
Let's talk about configuration first -
Since M4 barrels are out, that pretty much leaves you with two options: 16" "super light" barrel or 16" heavy barrel. (we'll talk about muzzle attachments in a minute) The Bushy super light barrel is pretty much just that - thinner barrel. Can't really flute them or anything. The heavy barrel can be fluted, if that interests you. Another option available is a Dissipator set up, where the carbine uses rifle length hand guards and places the front sight at the full sight radius as found on 20" rifles. Different look, and certainly has its benefits if you are going with an A2 config.
Speaking of sights, you also should consider if you want an A2 (fixed rear sights and carry handle) or A3/A4 (flat top, detachable carry handle, etc.) I strongly suggest you go A3 with the detachable handle as it will give you the most versatility if you decide to mount optics of any type.
Muzzle brakes - do you want one? I have or have had the AK brakes, the mini-y, the Armalite brakes, plain barrels, etc. If you are thinking of going with a compensator, let me know and we can discuss those in more detail.
As for manufacturer, you are definitely not going to regret going either route. Bushmaster offers a bit more options in terms of configs and available accessories but the Rock River warranty is nice. Then again, Armalite rifles are warranteed forever as well. I think you should decide on what config you want first and then compare the offerings available from each company.
Also, (here comes the shameless plug) you could join us for one of our regular NJ shoots. There are always dozens of different configurations there and you could try all of them out to see what you really like before buying. The next one will be in October and we would love to have you!
If you could give us some ideas on what configurations interest you, we could probably post pictures from our own collections to give you ideas.. Just ask, I'd be surprised if one of us doesn't have something you're interested in!
Again, welcome to the site! Its great to have another new member!