The advantages of a gas oven are a better broiler than you'll get in an electric oven and more moist heat for roasting meats and poultry and baking certain things like bread. The supposed advantage of an electric oven is more even heat for baking, but these days gas ovens are a lot better than they used to be. But I agree that if you're not getting a gas range, then stacking a gas wall oven and an electric wall oven might be a problem. I would choose your option 1 - but actually if it were me, I'd just get a gas range - I haven't been converted to induction yet :-)

I've only ever broiled in a really bad gas oven and a really really really good electric oven. The broiler in the electric one was better, but I'm willing to concede it might be better in a different gas oven.

You don't need a gas oven to have a moist environment for roasting or baking. You just need moisture. You can put a ramkin of water, or even a whole pan of it, in an electric oven and get moist heat.

Convection does improve a gas oven for baking, though electric ovens still tend to be more accurate and have less variation, from what I've read. That's probably comparing the best of them. It might be true that a less best electric compares poorly to a less best gas.

If your wife is the cook, let her decide. :)

Poorly designed gas ovens, working great in non convection, can struggle with convection if the fan effects the flame from the element. Don't see it so much anymore but some manufacturers are always trying to cut corners. Just don't go cheap on gas.