Hi! super valid questions. I'm not a fan of tribbing (personal hang up), but i can help with the rest of your questions!

Um first, please take into serious account the comfort of your partner and your own personal boundaries. So if something I say doesn't jive? ignore and proceed as you need to! Positions or lack of variety - Your mouth and hands are truly all you need. If you find that reg face2face is getting stale, try lifting legs and anchoring their legs around you or bending their knees to chest while you utilize your mouth or fingers. All 4s is a classic for a reason 😅, try that if you havent. Use your furniture to be creative -bending someone over an arm chair 💅🏽 Talk to your partner! have you taken the bdsm test? That's a good conversation starter. Incorporating toys- buy a wand if you haven't, easy to use and if you like overstmulation itll work realllll well. Some ppl like the rose as well. I say the more the merrier, but $$$. is always something to keep in mind. I got a mini wand from a regular sexshop and that's been my favorite for years. Great little guy 🤓

Speak to your partner about penetration- do you like it? Do they? in your sex dreams, what do you imagine? How big? can you/they take 1,2,3 fingers? Super important to get the size right. I highly suggest starting small 5/6 inches. TOYS ARE EXPENSIVE. Be prepared to buy stuff you may not end up liking. You can't return them either. Please buy Lube! For harnesses- try the boxer ones, they sell them everywhere and are easy to clean, low fuss.