If, as a political leadership, you inherit a national debt, you have to service it (pay the interest) and seek to repay it out of income, ameliorated by the effects of inflation. When China went more capitalist, privatising the state-owned businesses, they packaged up all the historic debt, allocated it to moribund companies, and sold the debt as equity. That allowed a fresh start. Clever folk, the Chinese.
We already have government bonds and all each government does is either add more, or repay old debt with new debt when interest rates become more favourable. So you could create a sovereign wealth fund, use it to raise equity by selling new bonds, repay the old govt debt via dividends from the wealth fund, and keep building that ponzi scheme for a while. then bust it and let the hedgies and investment banks take the hit. Maybe.
No political party/leader will solve all the problems we whinge about if they have to get re-elected every 5 years. You need a benevolent dictatorship with a longer fixed term of reign. Not something anyone would likely choose to vote for.
What does "real change" look like anyway? We still need an NHS, schools, universities, infrastructure, etc etc. All of which costs a lot of money which HMG needs to come up with through either taxes or investment returns. It's not too hard to design a new system if you have a clean slate. However there will never be a clean slate - as Reform have found in the councils they won control of in the last local elections. Great ideas and soundbites don't actually count for much if stuff still has to be paid for.
I can't see any possible party having an answer despite what may be desirable.