I myself consider VIE one of the best airports to connect at, but I agree that the fact that you have to walk the full way to the base of the pier (travelators only go outward) to both go to the lounges and more importantly to change between S and NS, is suboptimal.
Bus positions are not great, but at least they guarantee you arrive at the base of the pier.

All that in mind, I still routinely buy and make 30 minute connections Schengen to Schengen, which is pretty good going by my standards.
MUC is the best major airport in Europe to connect in, IME. ZRH is usually good, but it also has its issues, like the impossibility to cross clean between E and D (other than via Schengen) and the inadequate lounge complex in A.

Lounge wise, OS lounges are... average. nothing special. And at times prone to crowding, but which (non-F) lounge isn't? I would consider worse than current AF T2F (event after the degradation of level of service at opening), but better than old AF T2F lounges used to be.
That said, if you have the time, and means of access, popping over to T1 to the Vienna Lounge is advisable. One of the best lounges around.