For me it has been trial and error mostly, you kind of see what they prefer. Very amazing animals and the personality reflects them definitely. I've had Oli for 4 months now and have bought two cages, two wheels, and went through multiple different kinds of bedding.

Cage wise, I started with your first one, and realized shortly after Oli wanted more room.

This was what I have now, and I love it.

Guinea Habitat Plus https://www.amazon.com/dp/B001NJ0DQ8/ref=cm_sw_r_cp_apa_rVndzbSGFY140

Make sure you buy a large wheel, both the saucer spinners and silent spinners work great.

As far as bedding, I like the carefresh recycled cardboard. It's less messy and absorbs. My hedgie prefers the bedding, but that doesn't go for all.

carefresh Complete Natural Paper Bedding for Small Animals, 50 L https://www.amazon.com/dp/B00PBM761S/ref=cm_sw_r_cp_apa_t2ndzbJMEF9Y5

I tried a fleece and he wasn't liking that because he had nothing to burrow in. Make sure you have places for your little guy to hide!

Here's all of the stuff I got for her cage. She's 10 weeks old, I went a little overkill on the cage size (4 feet x 2 feet). It came with a fairly large second level, but I didn't put it in because I figured it would interfere with the heaters.  

Cage
2 - Clamp Lamps for CHE
2 - 100 Watt CHE
Igloo Hideout
Ergonomic Food Bowl
Bedding
Temperature Control for CHE Lamps
Carolina Storm Bucket Wheel With Pan
Chew Proof Water Bottle - Used this because it's glass and I had to mount inside the cage