The good money-back on the potions are damage magical regen, slow, paralysis and invisible ones. There's 2 other sets with giants toe and 2 without that nets 1000 for low to mid speech (they're at the UESP: Alchemy web page if you're interested).
After Faendal get you to 50 Archery, Sell potions to the Riften LA trainer. You're going to sell potions, buy levels in Light Armor (you need to since you rarely will get hit and because you want Light Armor wind walker) Sell more potions to get money back. Or you could buy levels in Alchemy with Arcadia in Whiterun. Make Magic weapons (or have the speech perk) to sell to the trainer/blacksmith in Riften if you want Smithing training.