As mentioned; the round object round simply needs to be a round player model instead of objects to eliminate those problems. If using correct player models, you would have the proper player animations and hitboxes and all; and there are plenty of fun and exciting player models out there; whether they be custom ones which players would have to download or if you don't want to add additional download files, default GMOD ones.
Also, oblivator really does have the best solution to this. Have it so after the 5th round in those 20 seconds of round end; have a quick menu box pop up for the server to vote. I think getting rid of this special round is not the best solution as it does bring something unique. Very few servers have this and the ones that do have this has no problems with their population leaving.