I just finished the game with my first character at level 28. She was NCR all the way and I deliberately skipped the DLCs (Ultimate Edition) because I wanted to do a first run-through and get a feel for the game. Hoover Dam was cool, really confusing at first because I was trying to figure out where/how to do the optional with the water valves but was too busy getting shot at so ended up going out the side door and to the camp. The Boomers flying over was pretty sweet.

I almost blew it shortly before that. When I reported back to Moore that the BoS was going to help, I got infamy and even though I was still idolized by the NCR, it triggered the Don't Tread on the Bear quest and then when I went out to guard the President, a Ranger started shooting me when I walked past her during my security sweep. Apparently that trigger is random, though, because I reloaded to when I walked in to talk to her and it didn't happen the second time. Rex made protecting the President entirely too easy. Love that dog.

Now I have questions. When I start my next character in a week or so, I'm going to hit the DLCs. From what I can gather, the recommended order is:

HH
DM
OWB
LR

Is that right?

I know that there are recommended levels for some of them, but are there any quest pre-reqs I need to do first before any of them? I'm still planning to do the MQ, but I intend to do a lot of wandering since there are still several locations I haven't seen yet, so I don't know when I'll get to the various stops that lead to New Vegas.