The Leaseholders as a group may be able to force the Freeholder to sell their interest in the building to the Leaseholders under the Leasehold Reform Housing and Urban Development Act 1993, that is, they may be able to “enfranchise” the freehold.
A group of leaseholders can nominate a purchaser or (more usually) create a Company through which they can jointly make the purchase.
The benefits are that participating leaseholders have full control of everything and are free to extend their leases to 999 years for £1 (i.e. a token sum).