I agree with the best of both worlds approach, that's what I do: have the QSO info box be the size of a standard label. I use Avery 8160 size, three per row labels. When I am sending out lots of cards, I used my DX Labs logging software to print out the labels. When I am replying or sending out onesy twosey, I fill in the boxes by hand.
Another alternative is GlobalQSL - check them out at
www.globalqsl.com. For 100 card batches, they cost you 13.5 cents per card, if you sign up for 1,000 it is 12 cents per card - and you just upload ADIF files, they print your card and send to the bureaus.
73 John K3TN