4K display support in OS X Yosemite

I just upgraded my late 2013 15" retina MacBook Pro to OS X Yosemite. At home i have my MacBook connected to a Dell UP3214Q 4K monitor. In OS X Mavericks 10.9.3 and later, 4K monitor support was much improved. The Display system preferences offered several resolution options under the Scaled option, allowing you to choose the right balance between text size and screen space. All those scaling resolutions have sadly gone away in Yosemite. Under Scaled, the only two options available are 3840 x 2180 and 1920 x 1080. Neither option works well with my Dell 4K monitor. 1920 x 1080 looks ridiculous on a 4K display. Defeats the purpose of having a 4K display. 3840 x 2180, which is the native resolution you get selecting Best for display, gives you the most screen space, but the text is so tiny and hard to read. I went to General preferences hoping I could increase the text size there, but that option is missing. So 4K display support has definitely taken a major step back in this first release of Yosemite. Please bring back all the scaling options we had under Mavericks!!