Ole hyvä ja kirjaudu sisään! Jos et ole vielä rekisteröitynyt, sekin onnistuu ohessa.
Bing's font and font size simply doesn't looks as good as Google's in my opinion. Bing's font is too big and is harder to read. I would switch to Bing if there was userscript that could make Bing's font easier to look at.
Look for existing CSS styles on userstyles.org, those can be installed as userscripts or userstyles.