Synthmaster is my go to synth. The engine in it is very powerful. It's run by a small operation and has constent new updates and soundpacks. They actually release new presets that mimic the exact sound of whatever producer used. It's really great because you can learn and deconstruct how someone gets a certain sound. If you produce dance music, it is MUST to have this.
I prefer to work with only a small ammount of synths because too many creates a mess.