Here's what I've learned so far... a few tips from a newbie to another.
1) When choosing feats for your new character, choose all the Luck feats. When you sleep, all those extra luck can help you avoid a lot of bad effects (like randomly cursing your items) and give you good ones (lots of new spells, potential and skill increases). And you can stumble upon money or materials when you are moving about.
2) Humanoid pets are better, as they can equip any extra items you have. Plus I've found another use for them - they know how good an item is, before the item is identified. For example, you have 3 suits of unidentified armor. Give your little sister the unidentified armor, one by one. See which one she equips. ID the ones she'd equip.
The problem is to know how pets choose equipment.
a) The AI likes to have all slots occupied. So give them some weak identified items, to compare with the unidentified ones -- then you know how good the items are, relatively.
b) I've never had trouble removing equipped items from my little girl -
either they avoid cursed items, they are not affected by cursed items, or their current item is always ranked better than cursed ones. I know I've sold items they won't equip, then in the shop's buy list, the items show up as cursed. Might need to do some tests here. Just read in the old official forum that pets will equip cursed items and would be affected. So the test is to see if basic non-cursed equipment is better than a high level but cursed one.
c) Random dungeon entrance dancing, as stated in the wiki. It's a bit boring, but that can help you get started.
d) I keep some basic items in my house as backup. In case I die too many times, I can use those to do random dungeon entrance dancing.
e) If it's not nailed down, it's yours. There're some decent furniture in the putit dungeon, and you don't need to fight any slimes to get to them. They help boost your house rank a bit for more salary.
f) Start the tutorial, but do not actually use the scrolls. The first few characters I've played I just left when the green haired guy said I'm ready for the world... don't. Talk to him again and tell him to leave. They'll leave behind some furniture -- once I got a two beds (boring and clean) and a shelf, and that's $3000 less I'll have to spend.