I would not describe Control as mostly somber.

Things about it that are somber / serious:

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• The formality of a government agency
• The overarching plot about Dylan and the quest about your home town
• The hiss
• The board
• Trench

Things about it that are whimsical:

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• Philip
• Ahti
• All of the documents and writing you find
• Dr. Casper Darling
• The mould
• Dr Underhill
• Jesse’s cool quippy demeanour when she gets through something or learns a new thing
• The Maze
• The music video tunnel
• All of the posters and announcements
• All of the generic FBC NPCs.
• Emily
• The former

Things about it that are both:

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• Northmoor

I have complete faith in Remedy, both of the Alan Wakes and Control have been surprisingly funny and whimsical, often in unexpected ways. Quantum Break had less humour and was a bit more self serious, but Microsoft also had more control of that project.