Member subs for the Tories are surely inconsequential both because their membership numbers are low and the amounts dwarfed by what they get from wealthy individual and corporate donors. And the most significant of those donors are going to have their own backroom influence on such things that won't be compromised by the loss of the local Conservative Club wine & cheese night.
Member subs for Labour were highly significant under Corbyn but are becoming less so now that Starmer has decided that a mass membership is more of an annoyance than an asset.
The other possible solution of course is for more people to become party members. If all the self-proclaimed sensible moderates who don't like the way extremist politics nerds run our political parties actually put their money where their mouth is, got involved and added their voice, you'd have parties that better reflect the will of the population, a more joined up democracy and voters who are better informed about how things actually work.
Labour subs are not expensive and have generous discounts for low incomes. Don't know about Tory ones.