Returning October 2024 for 4-5 day stay for a Kew Gardens multi-day visit, etc. Lift very helpful, laundry on site or as a service. Celebrating 61st anniversary so less 'power walking' but try to travel responsibly.
Do you have a price target or range? In £?
The other question I would have is why you want to stay in the Victoria area. Is it just because it's on the District Line to Kew? It sounds as if you have a fairly high budget. Kew and nearby Richmond are quite upmarket areas and have a number of hotels of varying price.
I agree that you could find somewhere really nice to stay near to Kew if that is the main focus of your trip. The Victoria area, although sometimes convenient, is pretty unappealing.
You could also stay in South Bank, which is a quick 5 minute walk to Westminster Station where you can take the District Line to Kew Gardens. No transfers needed and it's very easy.
Edit to add: I just realized you may be at Kew Gardens for several visits. If so, you might consider staying in Richmond, which is right next door to Kew, and is a very short bus ride away (about 5 minutes). It's a lovely town with a lot to see and do, including leisurely walks along the Thames, nice restaurants, hotels, Richmond Green, Ham House and so on.
We just returned from a May visit. We stayed 3 nights at Coach and Horses pretty much across the street from Kew Gardens. We visited the Gardens on multiple days (I got a membership+ guest). The hotel had a lift, but only to the first floor. The staff helped with taking our suitcases to our room which was up additional steps, and down a long hall. We enjoyed our evening meal in the pub/dining room as well as the full breakfast menu plus continental buffet. The particular room we had was small, but acceptable, with bathtub/shower (I always like the option of a tub). We did have an issue with the thermostat so that particular room was hot one evening when we returned. I think our room was the furthest from the front desk. I would stay there, again, as it was so handy to the gardens and the pier (took Thames boat trip from Hampton Court to Kew and Kew to Westminster with our suitcases the next day). We had a great meal across the street at The Botanist. There are a few nice restaurants close to the Kew station, also.
I would also love to stay in Richmond another time. We had a great walk and meal there, and enjoyed seeing all the shops. We enjoyed our visit/inquiry with the staff at the information booth in the Richmond station. We would love to do more walking along the Thames and up the hill further.