| Playing with a ukulele can be a lot of fun and sounds surprisingly good. I do it on a few songs with a singer I'm working with. I try to get the warmest tone I can by rolling the tone knob back and plucking the strings very lightly, and since the uke is a high register instrument, it helps to play a bit higher up on the neck to close the gap a little bit. This is also a good opporunity to break out the fretless if you have one.
As far as writing parts goes, it really depends on the song. The ones that we play just have simple strumming parts on the ukulele, so I have a lot of freedom. For those, I have found that a simple moving line played a little behind the beat works really well. | 
