IŽll try to offer some insight, as I have some experience of the same problem, but on my old E46 BMW (my current E91 has Xenons from the factory).
I had exactly the same dilemma and I decided to keep the Halogen headlights, but to replace the headlight covers. This was a DIY on the facelift E46 and pretty easily done. Not sure if that is possible on the E90. Made a HUGE diffrence on mine. If that isnt possible, you could possible try to recondition the plastic.
Two ways of doing that with some quick googling. Either using wetsanding (i Wouldnt try that) or by buffing them with a light abbressive like toothpaste.
When it come to bulbs, I swear by Osram Nightbreaker Unlimited bulbs myself. I had them in the E46 and I have them on my bike (Ducati MTS1200). They offer alot more light going down the road then the stock OEM bulbs. Phillips also have their X-treme Vision that are pretty good.
I havent the best idea on the halos or fogs. primarily because I dont spend time worrying about stuff like that. Its "all show" as Halos are concerned, I just changed my H8 bulbs over to some bargain basement blue ones and that is that. The fogs I havent touched, mostly because I dont use them. They just ad some light closest to the car, increasingt what is called "Self dazzling". IE: The light closest to the car becomes brighter, making your eyes adjust too much and you loose some nightvision at the extreme edge of your light throw.
If your serious about having more highbeam, you can go the route I decided on.
http://www.e90post.com/forums/showthread.php?t=1029961