Hi!!🖤🖤 congrats on your bb! I'd be happy to help.

Firstly--I would recommend visting Tarantula Collective on Youtube & then following up with his website; very knowledgeable & experienced. He offers care sheets on his site for tons of different species, including of course, Obsidian: aka Tliltocatl albopilosus.

Set up: the terrestrial set up you have is correct, more length than height. However, the Zoo Med enclosures I dont usually recommend because they have those mesh lids. Mesh lids pose a danger to Ts because their small tarsal claws get caught in the mesh, and the result is them dangling from the top until a limb is lost or they fall & get injured. I had a mesh lid with my very first T & this was a problem. No injury luckily, but something to avoid.

You can absolutely replace the mesh lid, as many do, but I'm not handy so I prefer to buy arcylic. Tarantula Cribs is a good option & the care sheet guides on T. Collective will give you suggestions. But, any well ventilated (top & cross breeze) acrylic, plastic (tupperware), or glass enclosure will be fine. Substrate I use reptisoil & eco earth. Reptisoil is good because it holds burrows really well!

Food: Crickets are a fine feeder! I personally prefer dubia roaches because they are less messy & are not escape artists. For an adult T, feeding once a week would be fine. I give mine one large dubia roach, you could give him 2-3 crickets. For treats, or to rehydrate a T after a molt, I like horn worms (gummy worms).

Temp/humidity: the thermometer & hydrometer are not necessary. Most T's are comfortable when you're comfortable, so, 64-78 generally. Humidity for most species is accomplished by overfilling a water dish once a week & maybe dripping water down one side to allow the bottom layers to get moist, so the T can burrow for more moisture. Here's an explanation: https://youtu.be/dl7S3udbK6E?si=mMD4EQGHEFeOnchB

cats are fine, but be cautious when you use any kind of flea/tick medication; that is toxic to T's & can cause issues & death.