My experience with the Reaper hasn't been great but that might vary from player to player. I was going to recommend dropping it but then I realized you're probably planning on using it with the stratagem to snipe characters and the like, right? In that role it'd probably work pretty well. Personally I would trade that Cronos for more Grots though.
I'm not a big fan of heatlances either but again, that's probably because they never do so well when I take them. I usually try to take cheaper guns on my Talos due to BS 4+.