Custom Clauses For Assured Shorthold Tenancy?

I’m about to renew an AST and wanted to know if any landlords on this wonderful forum have added any custom clauses to their AST’s that is not obvious/standard?

Out of interest, I normally add the following to my AST’s:

Custom Clause 1. No dogs are permitted at the property. One (1) cat may be permissible by the landlord with the landlord’s prior consent.

Custom Clause 2. Storing heavy items in the loft access area is not permissible as the loft area is not boarded. Tenants are liable for any damage to the area as a result of storing such goods/items.

I’ve heard of another landlord who inserts a clause to the effect that should a tenant end up receiving housing benefits, this is to be paid directly to him and not the tenant. Is this even legally binding to insert such a clause?

I’m simply trying to mitigate as many risks/problems going forward, as it’s complex enough being a landlord!

Therefore, your suggestions, recommendations, advice and comments will be gratefully received.

Many thanks

Mark