To me that would just look odd (funny). I would try to get a set of used AT's for the front, run the rears down and buy 4 M/T's.

Or get four M/T's and either sell the ATs or keep them as 2 good spares (this might mean you'd have to buy an extra rim ~$35).

I agree with Richard it won't hurt anything as long as the height of the tires are close.

This is just my opinion, take it FWIW
Ashby

'00 Rodeo LSE 4WD, 3.2, Black, LSD, OME 919s w/ 2in Spacers, Superwinch Hubs, RS9KXLs, Indy4x steel braided brake lines, LT 265-75-16 MT/Rs, ShrockBars, DOR HD rear Lat. Bar, MagnaFlow.