|Unfinished but usable|
I have a compelling reason not just for attempting this again but for adopting it as my default option: I often lose interest in a period before I can finish painting the models and I have boxes and boxes of unpainted and half-painted armies to prove it.
I was originally considering basing-before-painting as a plan that would allow me to get playing with a number of new armies/games, but I'm also now thinking of it as a solution to the lead mountain. It would also allow me to revive those armies which are painted but require rebasing. If I can play with unpainted or semi-painted figures, I can certainly play with unfinished bases.
Some clubs have very strict policies about playing with unpainted figures and I once fell foul of that in a previous life, but I no longer live under such a draconian order. Tabling unpainted or half-painted figures will be a huge incentive to complete them. I do however promise that I will play with unfinished armies only once, and will not use them again until I have done some more work on them!