No thanks! I regularly use this route to Glasgow, and arriving at Central is infinitely preferable to being dumped in the run-down east end because a) Central is well placed for the shopping areas and b) provides rail connections to multiple other routes, suburban, regional and long distance. I should perhaps add c) Central provides all the facilities expected of a major rail terminal, which I doubt any tram stop would.
As an aside, re-opening the City Union line (ie Shields Junction to High Street Junction) to heavy rail passenger services is regularly suggested; Last time it cropped up on Facebook I asked the supporters exactly what train service they thought would use the line, ie diversion of existing trains away from Central (again, as above, no thanks!) or additional (and therefore unjustifiable) trains - Not one person replied.
Surely the main reason anyone would ever come into town is to go to T J Hughes?
More seriously, it depends on the scope of the plan and how much money you're willing to throw at it. Glasgow has a lot of rail lines serving the city but run at very low frequencies. he Cathcart Circle, Paisley Canal line, North Clyde Line and Argyll line would be better run at a turn up and go frequency. Rather than traditional heavy rail you'd get far more from them by running them like a high frequency metro. Which is what basically any other European city would do.
As an aside - I've never understood the urge to run tram trains - the heavy rail lines already exist! There's no need for slower, smaller trains on existing lines.
Central is a bottleneck - we can't run a metro from it's platforms (or even at a significantly higher frequency) as is, and there's no prospects of a through service onto eg. the Argyll Line or the North Clyde Line.
You could divert the Paisley and Cathcart lines onto the Union Line and branch off to join the Argyll line on/under the obscenely large St Enoch Centre site. You've then got a big public transport hub in the centre of the city and less than 200m from Central that's integrated with the Glasgow Subway. You could even fit a travellator between them, but passengers for Central could just travel one more stop on the now frequent metro trains.
It's a huge investment, but you'd turn a disjointed and clunky heavy rail network across Glasgow into something modern and efficient. Passenger numbers would jump and you'd be able to get a lot of busses off of the roads.
Would the Scottish Government fund it? Probably not. But also I'm unconvinced that the tiny, gradual changes that the Scottish Government tend to suggest provide much in the way of value for money. Sometimes you need radical change.