Czech Republic

Depending on how much time you have in the Czech Republic, I say yes. We spent a month based in Prague and took a side trip to Brno. It's more relaxed and friendly than Prague. We spent a couple of days there.

yes. lovely little city and more than enough to see and do over several days. I have visited several times most recently in May this year, about 2.5 hours from Prague by train and about 98 minutes by train from Bratislava.

Yes .............

We are looking to stop for a day and night in Brno, on our way to Bratislava via a train from Prague.

Any recommendations for a RS type "hotel" in Brno?

I'm not sure what classifies as a RS hotel, but we really enjoyed the Courtyard (Marriott) in Brno. Rooms were very nice and the hotel restaurant and staff were excellent. My husband travels often for work and is a Marriott loyalty member, hence our reason for staying there. Compared to the Courtyard chain in the U.S., it was a delightful surprise.

Yes, Brno is worth a visit. It's a province capital and is on the way to the little place called Slavkov, better known by its historical name of Austerlitz, Napoleon's masterpiece battle in 1805 against the allied Russians and Austrians in the War of the Third Coalition formed against France . The chateau (Schloss Austerlitz) in the town center houses a detailed and balanced account of the battle. I saw it in 2016, went back in 2017 only to see the chateau in more detail.