You could always buy a used one, figure out for certain what you want, camp in it this summer and
fall, then sell it just before your new one is ready. You can modify what options you want right up until they start constructing yours - at least that is my understanding.
That is a variation on what I'm doing. Have a used one now to figure out what options I really want, what size I want, and what I can do without. Once I know for sure I want a new one, I'll order it, and continue to use the used one until I take delivery. These hold their value so well, and are so quickly
sold, that there is very little financial risk in starting used while waiting for new.