While this scenario is very interesting but still seemed too focused on England and little to nothing on both the possible Scottish pod to keep it Catholic and the possible implications from a Rome aligned surviving/independent Scotland that'd have their dynastic alliance politics.
Particularly if this TTL Scotland would still be a French ally and if as the England royals, they would wish/be able to marry with the Habsburgs.
Also, perhaps, would be possible that the more than likely possibility of inter -dynastic marriages with the Habsburgs would, (similar to the OTL, Catherine of Braganza), brought as royal bride's dowry some continental territories/Habsburgs domains.
And, even, more interesting would be the possibility that the Low Countries, as a whole or a part of it, would come in Dynastic union/personal domain (like OTL; Hannover) of the English dynasts... Though, dunno, as feasible, it'd be for the times politically and in genealogical/royal inheritance, terms...,