Is it best to put a uni as firm choice because of reduced offer?

do you have to firm it to get the reduced offer? if not then id keep it for insurance imo and pick whatever uni you genuinely like best for your first choice

that's fair, you've got till June anyway to decide your firm/insurance choices right
but I'd think you're likely to get higher offers than this, and firming a lower offer wouldnt be a good idea unless you've been to the uni and are absolutely sure youd wanna go there over any higher offers (if that makes sense) - means that if you absolutely smash your a-levels it wouldn't really count for anything in that scenario
have you had any other offers yet?

sorry for the late reply.
I applied to Lancaster, Sheffield, Liverpool, Loughborough and Bath
offers: Lancaster, Sheffield, Liverpool
rejected: Loughborough
not heard from Bath yet
At the moment my top choice is Sheffield's landscape and architecture dual honours, but I'm not sure if I like the city. I really like Liverpool as well.

The course is the most important thing to consider as that is what you will be studying for three years. If you can, go to an offer-holder day in Sheffield and have another look around. Head to the Ecclesall Road area where lots of students live in second and third years - it has a nice vibe. With two unis in the city there is a large student population and there is a lot going on.