Any ideas what to go for?
Could you be more specific? It's not clear what you're actually asking for.
What Tiagra groupset - there seem to be various different ones.
4700 if buying new. Exc value for money
Yeah, Tiagra 4700 is, I would wager, as good a groupset as an amateur cyclist would need.
@jackc started
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Could you be more specific? It's not clear what you're actually asking for.