I would prefer living in Muscat rather than Doha. Especially if you're married with kids. Oman is a very nice country and of all the Gulf states my favourite.
Career-wise probably better opportunities at Qatar. But I'm not sure what your ambitions are. Oman Air will be expanding their long haul operation. However I think they are more interested in serving the needs of Oman and not compete with Emirates for transit traffic like Qatar is trying.