well, under 20K you have multiple options. like 280x from AMD, then 960 2GB/4GB, 380 4GB are good cards
however, if you could wait for a month or two then you will have some aesthetic choices upon releasing AMD's Polaris in the market. which will probably comes in your budget too. or may be you will need to bump the budget little up. by 4-6K like Rx 460, 470. then rx480 as well.