J343 If you are semi-serious about pivoting towards Bonvoy then you could consider getting the UK Bonvoy Amex card that costs a £95 annual fee but gives you 15 Elite Night Credits (like you've stayed an additional 15 nights in hotels) which will take you to Gold Elite once you've got your 10 nights for Silver. There's a bunch of other card benefits too when you reach spending thresholds.

Thereafter, with the not-guaranteed-but-seemingly-annual double night promo you would need to plan (50-15 = 35/2 =) 18 nights a year in hotels during the promo period to attain Platinum.

Link to UK Bonvoy Amex

Important safety points: (1) I personally find Amex to be a frustrating waste of plastic in Europe and Asia as it's not accepted at anything like as many outlets as Visa and MasterCard but YMMV and this is not the place to ignite a row with Americans for whom it's a normal charge/credit card; and (2) as has already been briefly mentioned Bonvoy Silver and Gold membership will genuinely feel like nothing so manage your expectations of attaining these levels (and I mean manage them to zero expectations) because the real benefits like free booze and food in lounges, breakfasts, 4pm checkouts, notable room upgrades, being thanked at check-in for being an elite, only kick in at Platinum level.