I actually wouldn't mind this. If they do it it has to be Legend of the hidden temple.
I'd actually prefer the Temple Run being a bonus mode myself.
Unrelated but something that I like a lot about Nick all stars brawl is how many franchises is represented. Despite having less characters than Nick kart racers 2 (25 vs 30), All star brawl have way more franchise represented (With Ahh real monsters, Garfield, Jimmy Neutron, My life as a teenage robot and Wild thornberrys being unrepresented in Kart racers 2).
Something that's funny to me is that 7/8 of the franchises repped in Nicktoons Racing (not to be confused with Kart Racers) are in NASB, but at the same time the way most of them are repped is different.
Rugrats: NR has Tommy and Angelica, NASB has Reptar
Hey Arnold: NR has Arnold and Helga, NASB has Helga only
The Wild Thornberrys: NR has Eliza and Darwin, NASB has Nigel
SpongeBob: NR has Plankton, NASB has Sandy, both have SpongeBob and Patrick
Aaahh!!! Real Monsters: NR has Ickis, NASB has Oblina
Ren & Stimpy: NR has solo Stimpy, NASB teams him up with Ren and adds Powdered Toast Man.