Liked it? Yes. Thought it was corny? Yes. Thought the latter half made up for it in the most epic fashion possible? Absolutely.
Diebuster's quality is more consistent, no shit. It was great. But it wasn't better than Gunbuster. The cast was almsot entirely unlikable except for the two main characters. It went from "Super Robot" to "We're all just broken and magical for no explicable reason, deal with it" FLCL-style (which worked for FLCL, but this was supposed to be a super robot show), which entirely did away with any suspense to the battles. Humanity was depicted as an inept and conniving force that did nothing but conspire to make things worse for the main characters and
had absolutely no positive impact in any battle.
I love them both, but Diebuster was not superior to Gunbuster.