If you haven't already purchased the 744t, the new Mixpre-6 or a Tascam DR680, Zoom F8 or a used Edirol/Roland R44 should work fine for the application you mention, all at a lower cost. Hell, even a Zoom H4n Pro would work, so there are lots of options.
If you already have the 744t and your main application is a board feed plus 1 pair of (onstage) mics, the 744 really is all you need. The 744 has excellent built-in mic preamps, no need to get an external mic preamp. The issue with the 744 is that it only has 2 channels of on-board mic preamps, the other 2 channels need line level. If you are getting a board feed for the line inputs and use mics for the 2 mic inputs, you're fine. If you wanted to run 4 channels of mics, you'd need an external mic preamp for at least 2 channels since the 744 only has 2ch of mic preamps.
If you haven't already got the 744, any of the recorders above (except the Zoom H4n) have at least 4 channels of phantom power and mic preamps, so you could use any of them without an external mic preamp.