I have two suggestions:
How about making commander artillery load faster in singleplayer? In some maps, some flags which are heavily armed with machine guns, AT and AA are defended so well by the bots it is often impossible for the other team's bots to capture the flag. I often use the commander position's artillery to weaken these kinds of capture points, but it would add much more fun and ease if the artillery loaded faster.
The other suggestion is to make bots remain in transport vehicles like trucks or APC's. The bots do not get in the vehicle sometimes when I call them to. They will often only man the machine guns in APC's and will not get in when it comes to trucks.
Also when I manage to fill the truck/APC and drive, the bots will often quickly desert the vehicle even in the simplest rifle fire from far away enemies, spoiling my plans that initially got me to gather them in a transport vehicle.
I think these improvements would make singleplayer a lot more enjoyable.
First one could help re-balance some maps when playing solo, but the dev's also have to take into account Coop play which makes the artillery timeout all the more critical.
Second one. Good one ! Project Reality mod does this. So on APC's the gunner position is locked for the bots. Everyone else can get out but the gunner stays in. If you really want to rudely turf out the gunner then the player can switch to his position to kick him out. I'm not sure if it's possible to encourage bots to stay in vehicles. I think they do more in PR but I could be imagining that. To get around that myself when playing solo I rely on the squad respawn.
MY SUGGESTION: Add this python plugin to Coop/Solo to restore artillery and supply drops -
https://www.moddb.com/games/battlefield-2/addons/advanced-ai-commander-plugin