- If you want to stay 1 attack, the only quests that you need are those for Addy gloves, Horror from the Deep for Zammy book, and Dwarf Cannon for slayer. You should also do achievement diaries and One Small Favor for the xp lamps for slayer. Fighter hat and fire cape would also be nice to have.
- Slayer should be trained via cannon and ranging/maging or training def with the tasks when appropriate. Use the highest slayer master you can, and try to get as many xp lamps as possible (from achievement diaries, one small favor, etc.)
- Depends on what str/def levels you are looking to cap at.
EDIT: Forgot you can get up to addy gloves on an obby tank
You're going to want to get a torso and addy gloves; I'd start with 40 defence (dragon slayer is a fast way to get there, plus strength exp) and get higher as your strength gets higher, assuming you can afford things like bandos at some point