All mountains come with 1 deg side and 1 degree base .
Check with your manufacturer. Never Summer, for example, are 0/90 outta the box.
Like the others have said though, it is all a combination of personal preferences and riding style.
If you ride ice a lot you might want a sharper than 90 angle, say 1 on the base and 88 on the side = 89 degree corner. It will get duller a bit faster though. You might really like to carve hard and get way over on edge, so a 3 degree base and 86 side would give you the same 89degree corner but one that engages at a way higher tilt but will be slower edge to edge and somewhat sloppy in the middle.
A Zero degree base will be quick (even a bit twitchy) edge to edge, but very catchy and not too forgiving on any side slip.
If you ride in waist deep powder all the time, well....that just makes me jealous.
Personally, I'd say sharpen whatever angles are already on your board and ride it. If you find it catchy or hooky, detune a bit around the tips and tail. Just do a little at a time (maybe 1/2 a degree) because you can take it off, but you can't put it back