It wouldn't be the worst thing in the world for Allardyce to get another next year, get more 7th place results, and buy us time to figure out what we want to do long-term. The club could use some calm behind the scenes and having a manager see out his contract would help in that regard.
With that said, I can see the arguments against it. Another season with a 7th place ceiling will be near-impossible to sell to supporters, especially given the general feeling towards Allardyce right now. Also, what are the chances that Moshiri and his advisors do anything meaningful with extra time to plan? Maybe we're better off with Farhad buying as many raffle tickets as he can until he lucks out and finally picks someone worth a shit.
The difficult thing about where we are right now is it's hard to pick out anybody at the club with any sort of long-term footballing vision that might see us out of this boring, frustrating mid-table rut we're in.