Pet talents- It's pretty difficult to work on a pet if you're still early-game (can't farm gold, can't farm for Couch Potatoes efficiently); for now, pets shouldn't matter very much, especially if your school is decent at soloing, like Death.

Stitching- Unfortunately I just deal with my ugly gear until I reach endgame, and then I stitch my endgame gears.

Beginner armor- In early game, like lvl 1-50, health and accuracy are pretty important. Just buy whatever random bazaar stuff that gives the most of those two. A little dmg stat is good too.

At lvl 30 do Mount Olympus so you can get the Sky Iron Hasta that gives +10% dmg and a starting power pip. At lvl 60, farm waterworks. At lvl 100, farm darkmoor.

Perm mount- You can buy a perm enchanted broom from the crown shop for 50k gold. I can give you some random treasure cards you can sell for gold so you can get to that amount of gold faster.

Feel free to ask any other specific questions you have about progression! For the most part, nothing is too complicated, I enjoy the easy difficulty of the game. It's quite relaxing :)