Anyone here will only have been to one Uni - and therefore cant compare their Uni against any other Uni.
What suits one person, wont suit another. So asking for recommendations is not very realistic
Many 'top' Unis dont allow transfers mid degree - ie. you could only restart from year 1.
You will have to meet/exceed their A level requirements. So you cant 'trade up' to a Uni where you dont have the grades.
LNAT Unis will also usually insist you take LNAT - and its closed now for 2018.
And btw, I know it sounds obvious but you would still be doing a Law degree - if you are not happy at your first Uni is this really just the Uni, or was it the subject as well? Think carefully about this.