i usually don't bother getting repaints unless the original textures are ugly, or i can relate to the new paint job in some way (planes i've flown in real life and such).....
i did go out of my way to find every availabe repaint for the 737 experience though... i wanted to have it in all possible liveries (so far i've got about 15 variations)
also, there were times when i repainted aircraft to make them into something completely different, like when i got the B221 Monomail, i realized that plane would look really good as a Scrounger from the After World (one of my alternate realities.. it's a long story

), so i repainted it to make it look dirty and all patched up, like it had gone through repairs and modifications for a long time
now it looks real cool

c ya
Moach