Change the offline drone flight pattern from circling the base to a rectangular pattern extending from the town to the base. This would allow a better representation of online flight patterns over a base and town, and enhance practice ability in gunnery and ACM. 
+1
I've often thought having more options with the offline drones would be very useful and would allow for practicing a more realistic variety of shot angles. (I think I may have even suggested this a couple years ago?)
Perhaps in Offline Drones Settings (other than just the drone type), there could be:
1) check boxes for a variety of drone patterns
2) a slider (or check boxes) for drone speed, from the default 200mph up to maybe 300mph
3) a checkbox that would enable formations for bombers like what we see in game
As far as drone patterns go, in addition to the default 30-degree bank circle, I would like to see some of the following:
1) A "Racetrack" pattern, similar to what the OP suggested with long straightaways
2) A "Right Hand Racetrack" pattern, with right turns instead of left.
3) A "Lazy 8" figure 8 pattern, consisting of a right and left vertical turn at each end. Looking something like this:
http://mercury.kau.ac.kr/park/Archive/Aerobatics/lazy8_level3_flt3_269_310_.jpg
4) A "Vertical Racetrack" pattern with an Immelman at one end and a Split-S at the other end.
Just a few ideas.
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