I am a rank amateur at this but I bought the small Wacom tablet for the same reason, affordability. Personally I am very happy that this small one is available. Otherwise I wouldn't even have considered working with the tablet at all.
I am just learning to use it but I already like it far better than working with the mouse. Though small, so far I haven't had any big problems. I'm sure the medium would be nicer but for now I am very happy with this one.
1. Yes, for my work it is just right. Small like a notebook but large enough for the majority of my editing work, which is primarily spotting and working with curves. I do have to scroll around a fair amount at higher magnification but I was already doing that with the mouse.
2. Resolution doesn't seem to be an issue for me. To be honest I am not sure I can make an unbiased judgement here since I don't own, nor have I ever used, the larger tablets with the higher resolution.
My work area for digital editing is actually pretty small, so I don't have a lot of room to work in to start with. My Wacom just seems to fit into that minimalist space very nicely and it is easy to set it aside when I don't need it.