By Iberia you'd be lucky if even the top ranks of early Muslim armies in the west were largely Arabs. The North Africans supplied most of the troops and middle management AFAIK, and didn't take very long to largely absorb the higher postions either (already through the usual offices of intermarriage, politicking and generation shift).

Anyway, had the Moors not been beaten at Tours one sort of assumes they'd have been only too happy to drop by later for another major raid/reconnaissance-in-force. In Medieval (or in this case, Dark Ages/Migration Period) warfare enough of that sort of thing usually tended to result in the receiving side caving already due to economic damage and the other encroach on his territories. That said, the Moors had quite enough internal troubles (power struggles mostly, and the Caliphate -inasmuch it was in anyway relevant that far west- went Balkans over succession disputes around the same time...), the Christian holdouts in the more inaccessible parts of the peninsula were as annoying as ever, and while the Franks were the biggest fish post-Roman Europe had its share of other would-be empire-builders; it is a different question entirely to which degree the Muslims could have exploited a hypotethical victory at Tours-Poitiers.


As for Vienna, meh. Plain too far away from the Ottomans' main staging and mustering areas (Paris is closer as the bird flies, and the downright nasty geography of the Balkans added another geostrategic wrinkle); there's quite good reasons why their warfare in that front was mostly down to local clients, subjects and allies, and why they could project a full-out imperial army as far as Vienna only twice (and why both occasions bombed spectacularly). By the time they could get the army to the city the campaign season was already almost over and the winter cold approaching uncomfortably fast - and this with what amounted to the rank best and most effective logistics in Europe at the time.

Basically, Vienna was plain too far away and as such essentially out of the Ottomans' strategic reach; it's a testament to their capabilities they were able to seriously threaten it even twice. And had they managed to take the city, so what ? Their Central European opponents had a much easier time getting an army there from their "core" regions than the Ottomans from theirs; I'm guessing it'd have been a minor miracle had they been able to hang on to the place for even say five decades...

It's sort of the same thing why they could never polish off the annoying heretic Persians from their eastern flank (the Hapsburgs made something of a tradition of allying with the Shah whenever the Porte was getting unpleasant); out of reach and the enemy could enlist allies at the other extremity of the empire to boot.