If Conservative membership is really as low as 100,000, with an average age that suggests that number will only be going down in the future, there is an obvious way for anyone wanting to reform UK politics to achieve that goal: they just encourage a mass membership entryist campaign into the Tories of those who want to deliver real reform.
But then you realise that a) this is not a democratic organisation and b) the members have almost no say on anything within it.
At which point you realise why they're c) in such deep trouble.
And then you have to ask d) why they are so frightened of people and e) why they so publicly proclaim principles that they're clearly not willing to uphold.
After which you go back to the start and realise that this is not really a political 'party' at all and wonder why we tolerate it as we have done for so long when it's adherence to all the principles that UK democracy supposedly upholds so well is so tenuous.
NOTE: Jacob Rees-Mogg seems to agree with me: https://www.theguardian.com/politics/2017/oct/03/rees-mogg-tory-conference-like-north-korea-rally