Considering a new Wider field scope

[IDM]

I currently have an SW Esprit 100 (focal length 550mm) with flattener and a SW Equinox 80 (focal length 500mm). I use two camera either an Altair 26C or a Zwo 294 MC Pro.

After a recent outing where the Esprit with the Altair camera was imaging the Elephants trunk and the Equinox with the Zwo camera was imaging North American nebula I concluded that I need a wider field of view to encompass the whole of the nebula. Indeed the Equinox was my first telescope bought for astro photography and I have been really happy with, it but I think its focal length is too close to the Esprit. I am therefore thinking of selling the Equinox and buying a shorter focal length fast scope.

So far I am looking at the William optics GT71 (420mm focal length) or with 0.8x reducer flattener 336mm FL. Alternatively I also looked at the Altair 70 EDQ-R F5 which is a quad APO with built in flattener. The focal length is fixed at 350mm.

I quite like the Altair for simplicity of not needing to setup a flattener with all the back spacing optimisation potential issues but the William Optics offers 420mm or 36mm with reducer which might be useful when using it as a travel scope. I guess the WO could also use a barlow. I am not sure if the Altair can use a barlow.

Whatever I buy I want it to last a good long time so I am looking for a good quality telescope

Am I on the right track with these scopes or are there better other options. Does anybody who owns these or other suitable scope have any feedback?