Sadly, the consulates in Istanbul can't handle everything and I had to visit Ankara once. It was cold, wet, drab. Perhaps it would have grown on me if I'd stayed longer than a couple of days; perhaps I missed the bright spots and perhaps it sparks into life in the summer.
But I wouldn't return unless I had to, and I'd find it hard to recommend Ankara to a tourist over an easy to reach city like Izmir. Maybe you can even find somewhere of interest in Istanbul beyond Taksim !