If you're looking for a decent wash, I'm not convinced that the lights you have are the wrong tool for the job.
I'd start be figuring out what beam angle you need (assuming a 16' wide rectangle and a 30' throw, it looks like about 30 degrees is the right angle). Once you know that, you can determine if you have the proper lenses in your current lights, or if you need to swap lenses. If swapping lenses and re-aiming the current lights doesn't give you the results you're looking for, then, and only then, would I start looking at new lights.
If you determine that you really do need new lights, I'd take a look at the ETC Source 4 or the Altman Shakespeare (the latter if you are using GLA/GLC, or HPR lamps in your other ERS units) (and if you aren't using GLA/GLC or HPR lamps, you should be).