I've basically only been playing the endless mode and I'm almost out of space for books, which is sad. Not sure what I'll do once I no longer have any room for books.
It's a good simulator game, there aren't a ton of decorative or shelving options, and the system for obtaining new shelves is unique due to the game not having a currency, which meant starting out I didn't have enough shelves to organise the books I had the way I wanted, but that didn't last long.

Things that could be added/improved:
- If you miss the automated counters, that's it, you don't get another chance, which sucks in endless mode
- Some book categories seem off
- I'm sad that a lot of my favourite books aren't in the game at all
- Customers need help *a lot* which makes sense in limited modes but not so much in endless mode
- After about level 15 the upgrade options are the same every level, which is mostly fine but I'd like to see larger bookshelves so I can store more books, or maybe more room expansion options for more space