literally no reason to upgrade from a i5-6500 at this point in time if you're just using your rig for gaming. not even a 1080ti will bottleneck it.
Your system is definitely in need of a ram upgrade though. try looking for either a single 16GB stick clocked higher than DDR4-2100 so that you can just pop another in down the road if you feel like you need 32GB or go with the much more common 2x8 at the same clock speed. the games you said you like to play are games that devour ram so the faster/more the easier it will make it on your system.
1060 should be decent enough for the time being if you're on 1920x1080 but if you have anything better than that you should consider upgrading. 1070 kills 1080p and is decent for 1440p, 1080 kills 1440p and is decent at 4k, 1080ti is 60 fps in 4k for most games.
anyways, just my 2 cents.