Once Corbyn is dumped and a new leader, a press friendly one is found, policies have to be sorted out, but all must be sensible (Electable), and all must be very well thought out.
Free education for all - Nice start, but with no shit about abolishing private schools
Free NHS, including dentistry and prescriptions - Absolutely, but with no shit about abolishing private hospitals
Improving NHS efficiency, dumping tory business managers, and running hospitals as places for sick people rather than businesses - Yes please. As for private industry within the healthcare system - No, it's health care not a fucking business opportunity. Anything that can be outsourced can be done internally at a cheaper price.
Housing is an expensive mess.
Heavy taxes on all non-UK residents owning property in the UK, even heavier if more than one property.
Repossession of abandoned properties if the owners can't be contacted or they leave it in disrepair after warnings. These can be sold off and cash diverted to homeless shelters or whatever else is needed.
A building program as I described a few weeks ago. Cheap houses/rents will naff up greedy estate agents and force prices down, but provide a lot of work for builders, thus can be sold as business friendly.
Building cheap single room housing (with bathroom) for young couples or single people, probably for rent as council homes. Small is cheap to heat and easy to clean.
Homeless shelters in the style of pod hotels. Cheap but can help a lot of people. These can also be used to identify heath issues these people may be suffering from, and even provide free training so they have a better chance of finding work. A real address and email service can be provided at almost no cost, that giving these people a solid address to give to potential employers.
Roads - Massive tax breaks for EV manufacturers. This has to be backed up with renewable energy generation, and all sold to the country as promoting business opportunities and saving people's money, as well as being green.
Business gets scared when left wing Labour governments get elected, so sell the policy as business friendly and invite car and energy companies to the table. The tories aren't even close on this one so they'll be forced to copy, and it'll be obvious they're desperate.
It can also be promoted as forward thinking because North Sea oil is all but finished in not many years, so Labour can outflank the tories on that as well.
Everything should be built around helping people, never just for political ideals, and everything sold as business friendly and at minimal cost to the taxpayer.