"Junk" Food Question

Hi! I will be getting my very first hedgie the first week in March and I think I'm just about ready. I plan on eventually trying to feed a mix of high-quality cat foods with different meat sources, but know that I need to introduce them very slowly, one at a time.

I'm thinking of starting by adding Wellness Healthy Weight (chicken), then maybe Innova Light (turkey). Solid Gold Katz-n-Flocken (lamb) and Natural Balance Green Pea and Duck (duck) are also on my list as possibilities, but those have a higher fat content in them. Which finally brings me to my question...

I've heard that it's good to include a "junk" cat food in the mix, but I'm not exactly sure what qualifies a food as junk. Does that just mean higher fat? Or does that mean lesser quality ingredients, like corn? (I don't want more poop than necessary.) And I know some of the really crappy foods have sugar and artificial flavors, but there is so much other gross stuff in there that I cannot morally feed that...and sort of doubt that's what's meant by junk food.

So, what are some good junk food ideas?

I think you have a pretty good definition of "junk" food - the stuff with less meat, more fiber, etc... I'd stay away from the sugar and artifical components as much as possible.

My hedgie's "junk" food is Spike's Delite Premium. My her vet insists that Satin be feed "hedgehog pellets" and Spike's appears the best to fill that role. I'm also giving her Wellness Indoor Cat and CSCLS-lite as her staple kibble.

I have heard that Royal Canin 37/38 can be pretty junky. As of now, that's Hot Dog's "junk food."

I consider RC as the junk food in my mix. It is good enough to make the recommended food list so i can rest easy and know i am not feeding them anything detrimental to their health, yet at the same time the ingredients are not as great as things like CSFTCLS, Solid Gold, and Innova.
Its also notoriously tasty, just as a junk food should be . ( they spray it with fat before packaging, you can tell because the kibbles have a glossy appearance and feel )