Totaly hard to say- since....
For editing rasters, best I would say is Adobe Photo Shop project family. Yet, The Jasc , later Corel Pro, is good for rasters too, "but long time no see".
Adobe PS is an unfriendly soft that you will be speculating against, much, yet, it offers realy thrilling options for raster work, you just have to bite yourself a little bit (maybe?).
For vectors, SVG, or other formats, PS etc., and arbitrary deifnitions out of raster space, there are many vector editiors already, on many platfroms, but established editing program for vector 2d graphics would mayb be....? Long time no see. (ask graphician guys, I dunno)