My opinion OP, but I went to a local place here in OKC where they have something like 45 pinball machines to play. They range the gamut of classics like MM, a couple of EM machines, all the way up to and including a WOZ.
I'm in the exact situation as you as I will be spending around $3K for my first machine. I played NGG, NBAFB, MM, Nascar, RCT, WOF, Corvette, RBION, TS, DM, and JD. My very favorite out of all the machines I tried (which was about 10), was JD and TS. TS is extremely fun, and the upper "battlefield" is super fun and challenging. JD is awesome in it's own right with four flippers, a ton of shots, and the widebody is really noticeable. Good flow too.
Either machine, you can't go wrong with IMO. I've tried NGG a few times and I just can't get into it like the others. I love Lawlor pins too as a WW will probably be at the very top of my list. Just the NGG didn't appeal to me for some reason. You may love it however. Just wasn't my thing.
Keep reading as much as you can here. I've learned a ton just reading all the different posts. IPDB is a great resource as well. One thing, always search an ebay seller's name. There seems to be a plethora of sellers we should avoid.