1) Crafting can get you better gear in the early game, but drops and quest rewards will do you fine, imo the biggest bar to crafting is a lack of high enough quality tool kits and crafting, while good in its conception needs much more development to be any sort of viable alternative to quest and drop gear. But maybe that's the point as vertical progression in this game is designed to be minimal.
2)Mob difficulty is based on gear level not AP/SP earned, so they won't seem easier until you get better gear, although the right abilities and gear slotting will help. If you are dieing a lot look to get some passives that provide a self heal, a good early one is healing sparks in the fist section.
EDIT: also don't just slot damage gear, you will want a bit of health and heal gear if you are soloing, otherwise those passive heals just won't do enough.
3) Clothes do seem expensive at first but pax is easily earned, once you are in to the savage coast and blue mountain you should be able to afford additional clothing (it doesn't drop), although yu get clothes for all sorts of things like completing achievements and finding lore as well as completing decks.
4) Not sure what you mean here. Your total sp and ap points appear in the bottom right of the screen when you earn them, but if you go into your ability wheel or skill bar windows they disappear from your hud as these are just notifications.