4.56 hands down.
Guys that went 4.10 will tell you different.
You will run higher rpms than with 4.10's but the 4.0 won't mind at all and if you've added more stuff that adds weight it will actually be happier a little higher in the power band.
I ran 4.10's in my TJ with 33's and it was perfect but that had a Mercedes six speed. With your AX-15, I think 4.56's would be better. There are a ton of guys in here with AX-15's that had 33's at one time so hopefully you'll get a better response than mine.
EDIT: Never mind. Keith beat me to it.
Go 4:27s happy medium... 4:27S Are available for Dana 30, 35 and 44
I've had both 4.10's w/ both auto and manual trans and 4.56's in manual in the same rig and can say that the 4.10's were fine but while running the manual I preferred the 4.56's. It's not a huge difference but enough to make a difference. I definitely wouldn't say first gear would be useless...it'll be a hell alot more useful than your 5th w/ 3.07's! 
--Ian
You will run higher rpms than with 4.10's but the 4.0 won't mind at all and if you've added more stuff that adds weight it will actually be happier a little higher in the power band.
Higher RPM's than 4.56?
I ran 33's with 4.10's with no problems, now I am currently running 35's with 4.10's , still not lacking performance wise, I have 4.56's still in the box and don't think I'm going to make the change.
Higher RPM's than 4.56?
I said: You will run higher rpms (with 4.56's) than with 4.10's.
I ran 33's with 4.10's with no problems, now I am currently running 35's with 4.10's , still not lacking performance wise, I have 4.56's still in the box and don't think I'm going to make the change.
Do you have a manual transmission?
Can you use overdrive?
I have 4.10's in my YJ 4.0L 5spd with 33's if it wasn't for the fact my D30 was geared 4.10 I would have gone 4.56's when I swapped the ford 8.8 in the rear. I think my Jeep was perfect with 4.10's and 31" tires. 
Do you have a manual transmission?
Can you use overdrive?
Yes and yes, I run my jeep to the beach every weekend during summer months, I utilize 5th gear then as well as local highway driving through out Chester county, it runs like a top, i do not encounter speed bleed off that is annoying, yes I may need to down shift on long grades, but nothing out of the normal. as far as off road I stick it in 4 lo at RAUSCH, when crawling I use 4 lo 1st and hardly use clutch, I am able to crawl using mostly just gas pedal, competed in club comp and have no complaints what so ever
I Run a 93 4.0l MPI with an AW4 auto, I have 4:10s running 35s. Street, trail and sand is all good.. If I could go back and re-do, I think I would probably snag 4:27s.
I think my Jeep was perfect with 4.10's and 31" tires.
So did Jeep. Case in point is the rubicon that came with 31's and 4.10's.
I ran 33's with 3.73's and never "had any problems". But when I went to 4.56's I realized what I had been missing. Way more power through all the gears, could use cruise control again, (I know, not important to some but just because it's a Jeep doesn't mean driving it shouldn't be pleasurable).
I Run a 93 4.0l MPI with an AW4 auto, I have 4:10s running 35s. Street, trail and sand is all good.. If I could go back and re-do, I think I would probably snag 4:27s.
Auto vs manual = apples vs oranges.
Go 4:27s happy medium... 4:27S Are available for Dana 30, 35 and 44
Pretty sure there's no 4.27 for the TJ D30.
I've never heard anyone say " I wish I had less gear."
I ran 33s with 4.10s and loved it. 4.0 and 5 speed. But i was coming from my stock 3.73 gears after being on the 33s for a while. Changing from 3.73 to 4.10 was a move I should've made earlier than I did. that put me back in the same rpm ranges that I had when I was stock, sounds like you're used to a much different rpm range. Check out a calculator like this one to get an idea where you'd be sitting.
http://www.grimmjeeper.com/gears.html
With your current set up you'd be doing 2000 rpm at 74, and I was doing 2000 rpm at 61 (with 4.10s).
Or, in order to do 65, i'd be chugging along under 2200 rpm, and you're probably feeling sluggish under 1800 rpm.
But I can do 50 at under 1700 rpm whereas you'd have to downshift into 4th at that speed.
Can compare to 4.56 rpm/speed ranges. But, from everyone's replies, I don't think you can go wrong.
EDIT: I should add, I also had a lot of skids and a winch etc.
On my 03 Rubi I have stock gears and 33s.
Its okay . Still have power thru all the gears . I do have to down shift a lot if on the highway .
Average about 13mpg with them. 2200rpm at around 65mph.
If i ever decide to step up to 35s id prob go 4.88
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