I don't use Photoshop or GIMP much, but first of all, I'd get rid of that parchment color/texture and settle for an off-white/cream colored paper texture to start. While some modern maps use map symbols to represent mountains and forests, I don't think that's what you're looking for. So I'd redo all your mountains and forests to resemble more satellite view of real mountains and forest. Use the bump mapping feature in Photoshop to give the forest and mountains a slight emulation of depth with painted shapes. Then for your city/town symbols I'd go for the traditional dots of varying color for varying population sizes and secular capitals - dots or stars. All text labeling you'd pick some modernish simple font, serifed or unserifed - try both. The labeling should probably more closely resemble a modern road atlas map. It might be improved and appear more modern if you actually place some roads on your map, and perhaps include things like an airport or other modern features.