mono-stereo Aah, I hadn’t realised W had opened up a second location - I’m by where their first one is.
‘Mein Haus am See’ is also quite a fun bar round where you were if you want somewhere lively in the evening - it usually has DJs throughout; I played there often when I first moved here.
An enjoyable thing to do on the food front is go to the Käfer Restaurant on top of the Reichstag - the food is refined classic German fare, it has a nice ambience, and you get very good views of the city when you go out on to the terrace. Given the views I think day time is perhaps best.
It’s not cheap, but going for breakfast or appero (afternoon tea) is still reasonable. You need to book 24hrs in advance though I think, plus bring your passports with for the reservation; also breakfast spots might already be taken for this weekend, but it’s worth double checking.
All the menus and reservation forms etc are on the website:
https://www.feinkost-kaefer.de/berlin