No official price drop yet from Intel, at least in Malaysia. Don't get your hope too high here, we might not see any price drop after all 

It depends on the resolution you game at and the type of games you play. Some games like GTA V require a strong CPU as well as decent GPU. Most will require GPU. Remember though, a low end CPU will bottleneck a high end GPU

Er wait, you are talking about CPU right? If yes then it depends on the games, if it is heavy in CPU then you will benefit from a faster CPU, K or non-K don't matter if you don't overclock it but K series CPU is generally faster than non-K due to higher stock core clock speed.

In order to go for overclocking path, you need to prepare some "extra" budget for the components, an overclocked mobo (Z270 for latest Intel chipset or X370/X300/B350 for AMD AM4), a decent after market CPU cooler (new K CPU doesn't come with stock cooler anymore, even if it does include a stock cooler, it still couldn't cope with the amount of heat dissipated), a supported PSU (just make sure it is stable when you overclock) and etc.

If you're limited on budget, don't ever think of overclocking, the performance/price ratio is bad generally.