Well, if you don't want whats on offer, walk away! Neither of you can compel the other to do anything - it is a matter for negotiation, end of story and if negotiation is not possible, well then.............
If you have already had tow 4yr/11 month leases you still have your rights. The new law cannot change the past, it is for future happenings. Across the road -- was it 50k or 60k. A decent valuer should be able to find out the terms. The service charge element is probably part of the lease. You should be able to get that taken out if it is not part of a scheme or there are no other units part of the development. If there are you will just have to suffer it, in the same manner as the other tenants would have to.
If a commercial lease and with a Personal Guarantee from the directors, yes the persons remain liable. Otherwise if the business folds without a guarantee the debts goes with it down the pan.