Mercure

Mercure sits in the four-star range, a little above or below depending on the hotel. I'd call it the family version of Novotel: similar standard, but warmer and aimed more at leisure and city breaks.
The interior is warmer than at a Novotel, with warmer wood and softer colours. Comfort and equipment are very much on a par, and the breakfast is tasty. That makes a Mercure a great choice for a couple's trip or a family visit to a city, especially a longer weekend away. Examples from my stays are the Mercure Hotel Wiesbaden City and the Mercure Tokyu Stay Osaka Namba.
Because Mercure isn't built for business travellers, you rarely find a lounge. Upgrades to better room categories do exist, though, and I'm happy to recommend the brand.
Personally I prefer Novotel, because I like its cooler, more modern design. There are exceptions, though. In Warsaw, the Mercure appealed to me much more than the Novotel.