IMHO the best all round scope is the one you use most - and that's largely a matter of convenience.
Regarding SCT vs Newtonian vs refractor:
The f/10 SCT's are a jack-of-all-trades - able to do most things but not particularly good at anything. Their main advantage is a reasonable useful aperture in a very compact portable package,
Newtonians: The modern trend is ultra short scopes f/5 or less. These are basically "light buckets" with large aperture, best suited to deep sky objects (DSO) but not good at high magnifications (lunar and planetary, where you really do need a long focal length).
These take two forms: either dobsonians (an alt-az mount that goes up/down left/right and does not track the stars) for visual use, or bolt a Newtonian tube onto an equatorial mount if you are interested in astrophotography.
Pros: large aperture at low cost (bang per buck = aperture squared / price)
Cons: Probably have to realign the optics every time you set up. It doesn't look like "Ye Olde Telescope", the mirrors have to be cleaned and recoated periodically, and theres a pesky secondary mirror degrading the image quality.
Refractors: For those who are picky about image quality. I mean REALLY picky, and want to see nice perfect Airy disks around stars at high magnification.
Pros: Perfect images if you can afford an ED APO. Never have to align the optics. Cleaning is a doddle. And they look like "ye bloody big Olde Telescope" (if you can afford one of these
http://www.apm-telescopes.de/en/onst...or-110-mm.html)
Cons: relatively small aperture. Very expensive in terms of $ per square mm of aperture. A suitable mount is expensive, because of the long tube.
There are a few exotics, too:
Maksutov Cassegrains: Typically f/10 to f/20, these are better optically than the Schmidt-Cassegrains but are also more expensive and cost more. These are best suited to those visual observers of lunar and planetary things. Pro: good a high magnification. Con: they don't do low power, at all.
Schiefspeiglers: These are really specialist telescopes, they only have high power, and maximum power. Suited to planetary observers ONLY.