Don't bother with coma/flat field correction optics on an F8 scope, especially for visual. F8 has minimal to no coma in the visible field, so its not useful here. Save your coin.
Don't bother with a barlow, yet, unless it comes with the kit. Instead, look at a zoom eyepiece.
Use the basic eyepieces that come with it. When buying a new eyepiece(s) look at eye relief more than anything for comfort of viewing (lunar and planetary doesn't need wide field).
Really don't buy anything at all other than the basics, I would avoid all filters completely at this point. Anything too bright, just increase magnification and the brightness goes down. Just get out and view.
If you were to buy anything, I would argue for a zoom eyepiece, like a 7-21 or 8-24 flavor (1.25") for even more convenient viewing of planets and lunar surface (use the wide end to find your subject, then zoom in with a twist at will and don't fumble with swamping eyepieces, etc). Much more fun and convenient than swapping eyepieces and inserting barlows, etc, in the dark. I would argue for a Svbony 7-21, as this will get to 171x magnification which is plenty starting out with planets if seeing even allows, and as wide as 57x which is still low mag for a nice wide field still for hunting and cruising.
6" F8 newtonians are super forgiving, excellent scopes; not just a starter, a lifer easy. Inexpensive and yet a real scope with good everything. Far more critical is to simply get some sky time. Keep it simple so that it's not a chore. Minimize down time and setup time. Just get it out there and cruise.