Maris Otter, Vienna and Munich ( the light version from Weyermann ) are all great base malts for pretty much anything, except belgians. They will drive the colour higher up than regular Pilsner and 2-row.
I like Maris Otter and Vienna. Munich is OK, but not my cup of tea, although it works great in darker styled beers.
If you want crystal malts to use in APA, but much lower in Lovibond and strong crystal malt flavours, I recommend GNO ( Golden Naked Oats from Simpsons ), CaraBelge, CaraRed and Abbey malts ( all 3 from Weyermann ). All 4 can be used up to 10% without any issues and some of them, depending on your taste, even more than that.
I usually have CaraBelge, CaraRed and Abbey on hand just to use on lower ABV hoppy beers.