A lot of the issues I encounter are mostly related to Swift and SourceKit more than they are Xcode. The language server will start choking after a mildly complex project and highlighting and autocomplete will stop working. Sometimes it won’t recover until you delete derived data. Xcode itself is missing some modern features for navigation and a plug-in system however. I’d also like it if the Xcode team could learn what software patches are rather than releasing an 11gb version for every update.