sloped roof

the last option sounds interesting, and doable. I've taught myself to use a speed square, and can now cut decent angles. I don't want to cut any corners(like being cheap/skipping crucial steps, as ill be living in this for several years minimum), but don't have too much time left to learn ya know? can you give me a few more details of this method please? I don't mind taking a whole day to cut the pieces, I have an Ebay shop and am literally done at 10-10:30 each morning so I have time(daytime, but winter is near).

An arched roof is much preferred to a flat one. The flat one will nearly always sag slightly and then have a constant puddle.

My '98 coachmen uses simple welded aluminum trusses to get this bow shape. I think the rise in the middle is about an inch or two above the ends. I suspect you could build up simple wooden bow trusses without overly much effort. One approach would be to build up the bottom and top chords from two pieces of wood, glued together to form a T cross section, and then have a few thin plywood members in between them attached onto the vertical part of the T. You'd basically just need graduated heights of plywood bits. The top one should be glued together in a bent shape (use shims when clamping it) or it will be far too stiff to bend well afterwards (and the whole will be under considerable stress if you do get it bent).

You could also just use heavier plywood pieces cut in a segment shape, sketching the rounded top with a string and a pencil adjusted to give an appropriate outline. That is a lot of individual cutting; with e.g. a bandsaw it could be simplified by laying one out and pad-sawing a few at a time by stacking several strips of plywood and cutting them simultaneously.

if front to back set all the rafters in their spots run a tight string down the sides of them at the wanted slope then mark where the string touches and cut each stringer.

It's always best to have some slope so water doesn't just sit but either way will work.