To be honest, it surprises me they didn't have separate maps for the occupation victory...I'd have thought that method would actually have been easier...
As far as making occupation victory more "fair"...let's be honest, Sins is inherently an unfair game...even if we had perfect balance between the factions (which we don't and probably never will), the random map generator still is a dice roll that benefits some at the expense of others for all game modes...
A poor start has always been able to doom your chance of winning, and I'd argue that occupation victory isn't any more unfair than the "normal" conquest victory...the fairness/unfairness of occupation victory may seem more clear cut because it can boil down to just one number (the phase jumps between you and the star), but I don't think it is any more a dice roll than having a rough start that sets you back the entire game...
A series of heavy militia worlds between you and the star would be more detrimental in my opinion than having "one more phase jump"...call me a pessimist but I think trying to make occupation victory fair is somewhat futile...
That being said, it really sucks when the map gimps you, and though things may never be truly fair, we can always make them more fair than they are now...
I'd advocate more sweeping changes like a narrower range for dice rolls regarding extractor count and militia sizes...for example, ice/volcanics planets have 3 or 4 extractors (instead of 2,3, or 4) to reduce variability...neutrals could be changed similarly...and the militia templates could also be made to have less variability (terrans currently can have anywhere from 5 ships to over 20...really?)...
In regards to occupation victory, simply putting a more powerful Vasari force there would go a long ways (a higher level titan and an upgraded SB would be a nice start)...if no one can even approach the occupation planet until late game, I think it hardly matters how many jumps your HW was from the victory planet...