Actually, I would recommend you may first go to Andaz, since you can take Elizabeth line straight from Heathrow to Liverpool street station where the Andaz just right next to this station. Then you can move to Great Scotland Yard Hotel - The Unbound Collection by Hyatt for few nights. From this hotel, you can walk to some other major Tourist spots like Trafalgar square to the national gallery to China town, or pass the 10 Downing street to big ben and Westminster Abbey and possible Buckingham Palace. Both are good for different reasons. Other than those two Hyatt properties, personally, my favorite Hyatt in London is is Hyatt Regency - the Churchill which is about a block behind the locals' favorite department store, Selfridges. That area have more choices at night, especially. If you really preferred stay close to Buckingham Palace, I would recommend St. Ermin's Hotel, Autograph collection by Marriot. Their rooms are renovated in 2021. Their service is good and their restaurants provide more affordable foods too. But that location is quiet at night. I have stayed a night or two in all the above hotels in London last summer and this January.