I like this one. It's called "Cats in Cubes" by OneFastCat. Currently they are out of stock until August 1. I think they are cheaper on Amazon, but they may be out of stock too. you can keep adding to it, and build it in any shape you want.
Link is my new goddamn hero.I love the Kitty Mansion line. Deluxe Cat Trees
Their warehouse is near my house and I was able to check out their showroom. Plus I got a discount for buying directly from the warehouse; but they do sell through Jet, Chewy, etc so you can shop around for sales. The deluxe line has larger posts and platforms which is perfect for Link who likes to hang onto the top bed of his and kick the post (I think we have established Link is special). Link is a medium-large cat who is a very long 13 pounds. The tree has a little box/cave that Link can't fit in but Rocket (who is 8 pounds) has claimed it as her scardy cat safety cave so all good.
Pay no mind to the bald spot on his arm in the one photo since he decided a spider bite would be fun experience. That was right after he broke his leg and that was right after he decided to fight with a raccoon and got bit. Link is a trouble child... but no vet visits for the last 6 months, yay!
The platform Rocket is on in the second photo is big enough for Link to nap on. He leans up against the book shelf and passes out almost every night on it.
I know someone else got the Kitty Mansion line for a very large cat and he fits with ease. Kitty Mansions Cat trees
There is this thread with lots of cat tree photos that might help you out with selection too:
pictures of Cats enjoying their cat trees
Link is a special child.
Have you tried OneFastCat.com hamster wheel for cats? It's the first time my has tried it. Already she is trying to get the wheel to go on her own! Cat Exercise Wheel | One Fast Cat | Cat Running Wheels
I don't know about perch sizes, but Armarkat is the best big name brand available from my experience. There are a few small companies who make better, but for a huge price premium.
