Makes no real difference IMO, I think you're making a mountain out of a molehill.
Nobody will be changing their open raise sizes in these games just because the SB isn't quite half the BB. They'll still open for 2.5BB, 3BB, 5 or 10BB, whatever is normal for them. If you choose to call or raise them, then you'll be putting in the same as you would have in a "normal" game.
If it's limped around to you in the SB and you decide for whatever reason to just complete, then you'll have put 1BB into the pot. As opposed to a "normal" game where you'd... also have put exactly 1BB into the pot. Can you see where I'm going with this?
The only time it makes any real difference are the times when you fold preflop from the small blind (which will be a lot of the time given it's the worst position at the table, right?). On those occasions you're actually saving money compared to a "normal" game since the SB is smaller.