Filler.

I don't think you really missed anything. The three modified souls were created by Urahara to scout for the Bounto, but they still hang around a little bit. Kariya, the leader of the Bounto appeared when Ichigo was trying to master his inner hollow, but besides that, there's not much of importance that you missed.

http://www.the-fanboy-perspective.com/

I guess you should watch those fillers you skipped.

Metallica and Iron Maiden are Bronies

Best to look up what eps may have something important.

The show has a crap ton of fillers to where even the important eps can be filler like.