I very much like my Lenovo thinkpad laptop keyboard. I like the compact layout, proportion and sturdiness of it. Do you think I’d be happy with the Keychron?
That is indeed very compact. I like compact keyboards too. You didn't mention gaming so I'm going to assume you don't care too much about that.
If you live near a Best Buy, pay one a visit, they usually have keyboards on display which you can type on. I suggest trying at least the following:
1. Logitech MX Keys Mini. This provides a very nice laptop-like typing experience.
2. Logitech G815/915. This is a "gaming" keyboard with low profile mechanical clicky ("blue") switches.
Based on that, you can decide if you care about mechanical switches or not. If you really like the low-profile clicky feeling, the Logitech are great, but wide compared to your Thinkpad, and also expensive (>$200). Keychron has narrower versions with lots of customizability. There's some other vendors too, here's a list [1].
If you prefer the laptop-like typing experience, the MX Keys and the new Mini variant are very popular, for a good reason.
You’re in luck! There are a number of USB Lenovo thinkpad keyboards with track points, and sometimes trackpads in full and ten key-less formats. (I believe it’s also fairly straightforward to convert a ‘replacement’ x220/x230 keyboard to USB).
Here’s a couple of model numbers to get started:
FRU 0B47221
FRU 40K9427
Some of the features to consider (by no means exhaustive):
1. Width: 60%, TKL, or full-size
2. Height: Normal or low-profile
3. Key layout: Ergonomic, ortho, staggered
4. OS-friendly layout: Mac or Windows
5. Switches: clicky, tactile, linear
6. Misc: RGB, programmable keys, wireless
Personally I like 60% low-profile clicky keyboards. I use a Keychron K7 at home and MX Keys Mini at work.