Soldering SMD's by hand is easy... I do that all the time...
But yeah, I know it's not for everyone...
But on the driver part... I think it's an excellent idea to make it a port out to a daughtercard...
LouMan, vibration isn't an issue, just stack the cards on top of each other with spacerbolts and a pinheader... I have done that several times in applications for dragsters/funnycars and similar... Then you can talk about vibrations, and it's completely problem free since the cards go dangling in sync...
I agree with adamj12b, a serial interface to plug in an external "screen driver" would be a much better idea... Why not use the daughterboard idea here too? Make a second port for a small daughther board that reads the serial data and reconfigures into whatever graphs you would like and then sticks it on a display? Much better than loading down the main CPU with that task...