Some background first:
I currently own a 10" Orion Intelliscope. This works great for visual observation and I've seen a lot from my background. I typically use a 13 mm eyepiece; given the scope's focal length of 1200mm, this gives a typical magnification of about 92X. Since I typically looks at clusters, nebula, and galaxies (and will continue to target these types of objects with my EAA), this magnification seems to be right in the sweet spot. The Intelliscope tracking also tends to put most objects in the FOV at this mag as well.
I want to take a jump into EAA after seeing it first hand at Lowell Observatory in Flagstaff. My first thought was to use the same 10" reflector OTA from the Intelliscope and put it on an alt-az GOTO mount. Quickly found out that the OTA is far too long and heavy for most mounts and it would be at least $1500 for this mount. On top of that, the focal length of 1200mm is quite long for the entry-level EAA sensors. The ASI224 and ASI385 are like 6mm and 8.4mm eyepieces respectively, giving mags of 200x and 142x. I would prefer to stay around 100x for this EAA setup.
After much reading and thinking, my ideal starter EAA setup would consist of a scope with a focal length between 650mm and 950mm. The ASI385 camera ($330) or the ASI2224 camera ($224) would offer mags between 90x and 110x (the purchase scope would determine the final camera choice). Another important spec would be the f ratio with f/5 or less being the goal. An alt-az GOTO mount is also required (equatorial can also work). Finally, aperature is nice with bigger aperature's collecting more light and showing more detail - but aperature, focal length, and f ratio are linked - it seems 5-6" (130-150 mm) will be the aperature best matched with the focal lengths and ratios listed above.
It seems I have choice between reflectors and SCTs.
On the reflector front:
1. Orion Starblast IV 150 mm - FL=750mm - f/5 - I've heard this OTA is on the cheap side with plastic mirror components - comes with GOTO alt-az mount
2. Celestron Nexstar 130 SLT - FL=650mm - f/5 - Smaller aperature than the starblast but better made I believe - comes with GOTO alt-az mount
3. Celestron Omni XLT 150 - FL=750mm - f/5 - OTA only - seems like a great choice but what mount would be best?
On the SCT front, the choice is a Celestron Nexstar:
1. The 6SE has a FL=1500mm. I'd need to buy a f/6.3 focal reducer giving a FL=960mm.
2. The 5SE has a FL=1250mm. Still need to buy a f/6.3 focal reducer giving a FL=800mm.
The reflectors will have smaller secondaries which seems good for light gathering. The SCT's will be more compact and balance better on the mount, but will be more expensive due to the need for a focal reducer ($100).
What have I missed? I'd love to hear advice or recommendations from anyone. Why should I choose a reflector? OR, why should I choose a SCT? Are there other alt-az mounts out there that would be good for these types of scopes (especially the Omni XLT 150)?