I would honestly just leave everything at this point. As long as your ammonia doesn't get super high again you should be fine (I've read that excessive ammonia levels can encourage the wrong kind of bacteria). Your seeing lots of nitrates which means your on your way to completion. I would add a small pinch of fish food every day so that you keep your cycle going, and just wait until those Ammonia and nitrite levels are down to zero before adding you're fish. Once its all Nitrates, do one big fat water change and then your good to go!
Props on being patient and doing a fishless cycle. You really have a lot of leeway doing it that way....sooo much less stressful!