LQ South is the best in town in my opinion. If you want pure cheap with transpo, LQ North is available and the people watching is choice. Hooters Hotel offers cheap airline rooms and is at the end of the strip close to the airport but I don’t think they have a van anymore so transpo would be on you.
Honestly, there are almost always cheap rooms there. Finding a ride and the hour long wait at zero level are the biggest challenges in LAS.
I don’t know anything about long term. There are some crash pads run by SWA pilots.