Maybe some battle selection scheme based on "named commanders" ... only battles where an commander is present may be controlled detailed and all others allow only an lower level of control. May be there could be an special, low budget per player to create an new named commander in critical situations.
Simultaneous battles may be more easy to choose and handle if the choice and control gets limitedby an in-game factor. Multiple low-control battles overviews may be displayed at the same time.
Some time-waste may be nullified by overlapping gamephases:
Two main phases in a turn: empirewide orders and battle orders First phase is the empire wide orders with an additional deadline on battle declaration. After that deadline the engaged players may switch between battle orders and empire orders. Thus unoccupied players may micromamage their empire, design new ships, ....
Dragoon - firstname.lastname@example.org - sorry if wrong place for comment
- It isn't "wrong" to comment here, but you'd likely get more responses and have more influence posting on the forums in a relevant thread. -Geoff