mics I like better for less money:
AT2020
AT3035
Shure SM58
Shure Sm57
Must I go on? Basically the mic was great when it was one of the first low priced condensers, but it pretty much sucks compared to the current competition.
In order, from lowest price to highest price:
MXL 603s
Octava MC012 (if you can find matched ones)
AKG Pro37 (much underrated)
AKG Blue Line Series (trust me)
AKG c451b
Groove Tubes GT40 (improved version of the GT44's that have been raved about as overheads over at gearslutz.com)
AKG C414eb...
You are right that the AT4040 has a flatter response than the 4033, and IMO it is a little more versatile than the 4033. Both are great mics. For lead vocals, flatter is not necessarily better. I've done a lot of recording with most of the mics mentioned so here are my thoughts:
4040: Great...
IMHO you cannot beat the Firebox for the money. INSPIRE seems to be pretty awesome also, and even less money. I've spent a ton of time with an MBox before and the Firebox was a real lifesaver.
It's good if you can't mic up an amp. It also is useful to add into tracks that were really recordings of an amp. Great efx, etc. Like everyone else has said you really have to take the time to tweak it. It's a pretty good item to have in the studio though as there are a lot of uses.
Groove Tubes Brick for around $400. You could also use it as a DI when needed. Nice tube sound while still remaining open.
If you look around you might also be able to find a used Vintech 1272 for that price, but I don't know if I would want that as my only preamp. It's a steal for the money...
I like soundcraft, but I think those Spirit mixers - at least the ones I tried - suck. M series is OK and the ghost is really awesome in my opinion. I do like the Firepod also.
Both are great mics to have. The e609 rocks but there are times when I end up using a 57 instead. I actually combine the two alot. You should probably go ahead and get one and plan on getting the other later. The 57 might be a little more verstatile for you.
Unless you're doing classical music or something similar you will probably be ok to match them by ear or two get two consecutive serial numbers. The AKG stereo kit is very nice though.
A-designs (I think) also makes the ATTY. It's two channels with a knob so that you can adjust exactly how much you want to attenuate it. Very nice unit.
The AT4040 and the Shure KSM-27 are very flexible mics. It would be nice to have a pair of either of those.
The AKG C414 B-XLS is also a very versatile microphone but is a little expensive in relation to your budget.
That is pretty sad that after a week the order still has not been put in. On the other hand, I've heard several times lately that Avalon is extremely behind.
Neumann u87, u67 (tough to find one in good shape), u47 (same problem), Lawson L47 mp (www.lawsonmicrophones.com), All of the Soundelux high end stuff, Brauner, and I probably left out a ton. But those will all be pretty good stuff. In your case you will probably want to go new, which will...