First off, the Ultra AI (super AI??) option sets the skill level of every AI in the game all the way up to 1.
I don't like it that much because it means the player tends to get shot through bushes/rocks/trees/buildings etc.
Now here's my 2c on the AI situation...
I think that to get good AI behaviour (eg. doing different things depending on the situation), it's really up to the mission designer to factor in specific options for the situation.
There's no silver bullet... no 'solution for every situation'. Whether you use a script, or cycle/move/Search and Destroy/Sync'ing waypoints, there is no substitue for tailoring the AI behaviour to the specific situation presented in your mission.
My advice is to put yourself in the place of the enemy commander. How would you accomplish the objective and defeat the player? Would you try to get around beind him? Would you have one squad hold position and fire while another one moves up?
There are plenty of missions out there that increase their difficulty simply by adding
legions of bad guys. The trick is to make the mission hard using
position and placement, rather than just numbers
It's all about thinking outside of the box and being creative.