Regarding the Empire - I'm using Cemiess - 6 Empire Factions. Ranked up to Allied with all of them and the good systems closest to it:
Coastakal (3 Emp), Vequess (3 Emp), NLTT 7789 (3 Emp) etc
Condovichs and Wongkamala both have 5 Emp factions but are in a state of war, so it can get a bit hairy bulking missions to them.
Running data only missions at the moment until the courier bug is fixed (sent to another sys where you can't hand in the cargo, meaning a fine and stolen goods) and ignoring the extra time 0:00 message bug for data missions.
Doing the low end charity handouts as I've tried all price ranges up to 750,000 with the same 1% results.
Been doing some tests and, probably because I'm at Lord rank, I've only seen a 2% increase happen a couple of times.
On 30% Lord so shouldn't be too long now till I get that Clipper!