I never stayed at the Intercontinental, due to the location.
The Holiday Inn is more intimate and has a much better pool.
The Crowne Plaza feels like an outdated grand dame hotel. It's more elegant but not as relaxing, and the pool is an afterthought.
Both are perfectly fine options. If I was simply looking to party, the Crowne Plaza is tough to beat. If I was going for romance, the HI would have the edge.