Return trip to London - where to stay?? :)

Both the South Bank and Bloomsbury are very central. On the South Bank, the Premier Inn County Hall is very popular with many forum members. It is a chain hotel. Premier Inns don’t have much character but they are comfortable and usually a good value. It is close to both the Waterloo and Westminster tube stations. I lived on the South Bank for a year when I worked in London and loved the convenience of the location.

In Bloomsbury, I like the area around Russell Square. This area ahas more charm than the South Bank. I’m staying in this area on my next trip but can’t recommend a particular hotel as the place I have chosen is new to me..

With a family I would look on VBRO for a flat.

I'd recommend checking out the Locke at Broken Wharf. They have large rooms with kitchenettes and washing machines, and the location is very convenient to Blackfriars tube station and à couple of others.

I don't know if you aware, but there is an attraction at Battersea Power Station where a lift takes you up inside one of the iconic chimneys. The emergence at the top is a real WOW moment. It's called Lift 109, there is a charge, but slightly cheaper if booked in advance online, I think it's around £14-£22 per person.
https://thechimneylift.co.uk/tickets/?gad_source=1&gad_campaignid=23248097997&gbraid=0AAAAAo7d-nb-zFe5Xp_EZ7SJ_mfUUvNoW&gclid=Cj0KCQjw3qLSBhDaARIsAFTiVh5q5UOYNlSHaQxFOkoT5gQcAHS6rWxcvSv4zG79aNAJeKul7V9P2roaAgucEALw_wcB&tx_inline_iframe=%2Fdate-selection&tx_sessionDataId=3b715047-cb26-49d0-b174-6fbd634c2b8a

I'll echo jphbucks suggestion. Locke at Broken Wharf is my go to place to stay. If you desire a river view book those rooms, the city-view room look onto buildings to the side and away from the river.

Premier Inns are all over London and reasonably priced. We stayed at the one near Victoria Station last year.

I liked our premier inn Waterloo Westminster bridge. Just a few blocks from the County Hall PI but a little quieter area I think being farther from the river and London Eye etc.

I understand that the canon here on RS is to promote Premier Inns, but I've never had a satisfactory stay at one. My experiences at the Ibis chain have been better.

Just another viewpoint.

I usually stay relatively close to the train station I plan to depart from so that I can walk there with my luggage without taking the Tube. If you're leaving from St Pancras, Bloomsbury is a good choice.

JMHO, the reason posters recommend Premier Inns is that they are affordable, and they have locations all around London.

I have stayed at Premier Inns near Earl's Court and Tower Hill. Both worked well for me. PI's offer early check in for a small fee,comfortable beds, and flexible rate options.

For travelers who want hotels with character/ambiance RS posters usually offer recommendations for those as well.

When I take my kids to London we nearly always stay at a Premier Inn in Southwark. There are a few locations. You can walk to the West End if you don’t mind a bit of a walk and the South Bank is on the doorstep. Plenty of restaurants around.

County Hall and Waterloo PIs took early luggage drop off, even though we didn't do early check in.