A monocular is basically 1/2 a pair of binoculars, so it needs to be hand-holdable as it is designed as a portable device.
A spotting scope is built for power of magnification & sharpness of image. It is (compared to a monocular) huge & not easily portable as it is designed to be attached to a really solid support & not moved in use. That's why they come with some kind of tripod as well.
OK part of the problem here becomes the laws of physics.
High magnification & high image quality mean honkin' big front end glass, much bigger than a monocular would have because of the portability problems it would cause. The rough rule says that you need a
minimum of 1" of front glass width for every 10X of magnification, this limits the designers so they simply lie about the "power" of the scopes 99% of the time. Will a small diameter scope go to 100X ? Sure, but the image will get fuzzy before you get there so anything over 30X will be so fuzzy as to be useless, (except for advertising).
(The "hump" is usually prisms designed to fold the light path within the scope to keep the length down to something reasonable BTW, if they weren't there a good spotting scope would be 6~7 feet long).
So if you're going to try for both you have design limitations you're going to
have to deal with.
How much of a compromise will you have to make? It's up to you but I would suggest really try before you buy under field conditions before plonking down a lot of cash.