In reply to joe86:
Do you have transport (a car), to take you places, or are you restricted to starting and finishing in G-on-Spey? If you do have transport, you've got loads of options in the Cairngorms. (There may be buses from Grantown to Aviemore/Coylumbridge, but I've always had a car when I've been in the area.) There's very little snow at the moment, and any that is lying can either be avoided or walked on (with the obvious exceptions of any lingering cornices).
For ideas, you could do a lot worse than look at the walkhighlands website
https://www.walkhighlands.co.uk/ and Steve Fallon's website
http://www.stevenfallon.co.uk/ and of course the route cards on UKHillwalking.
Paths may or may not be marked on maps. Most of the major ones are marked on the OS maps - you may find they're marked as dotted black lines, rather than the green dashed rights-of-way you might be more used to in England. As you say, access laws are different, and you can make up your own routes more easily than south of the border, but sticking to paths does make life easier.