Sell the potions. I stacked mine up for years only to sell most of them. Depending on servers, the Draconians can get you a decent amount, but probably not anymore.
Alexander items: turn them in for gear to keep or turn in as well.
Crafting items: See whats worth gil and what is not. If it comes down to space, sell the cheap stuff and get it when you actually need it. Trust me, the inventory spot is worth more than a gil or 2.
At the end of the day, with only 2 retainers, you reeeeeallly need to prioritize what you're gonna keep. My advice, keep only what you know you will use or use soon, and ditch anything cheap. If it's a job you wont level for awhile, turn in the extra gear, youll always get more gear in dungeons.