I have been using straight for a while now and I think it is great! The ability to lazy load everything by default does a lot to make Emacs snappier (or at the very least, faster to boot). Being able to pull packages directly from git (be it local or a forge) makes package development a lot easier. raxod has a lot of really sleek, modern emacs packages that I would encourage everyone to check out, selectrum[0] and ctrf[1] in particular are really great as well.
You can get autocomplete for Java methods in Cider (Emacs) and probably Cursive (Intellij) afaik. Type checking in intro code can be a bit difficult, but REPL/live development really helps. You are going to catch mismatched type at first call, so you can usually get there by reading the Javadoc, but it does take some practice. Most Clojure code also works with Java through the smallest interface possible at the edge of your system, so it is very rare to have to deal with those issues in your "main" code.