How come when I do a quote for a 1.4 over a 1.2 it comes back cheaper same year same car just 1.4 instead of 1.2 LOL find it very strange. Also, may be mine is just a freak of nature or something but I do not find it vastly under powered (even before the mods) not that its vastly powered now, I am not doing quarter mile drag races with it LOL. I test drove a few cars before buying what I did. Anyway each to their own.
NOTE: (not arguing this same topic again

).
TBH the 1.2 and 1.4 will be vastly underpowered compared to TJet or MultiJet.
Anyways, back to the OP's actual question the best thing to do is read the FAQ's and Faults and Recalls. That will give you a better idea as to what to look for when going to look/buy the one you are talking about.
In terms of GP's being slammed, a few that come to mind are
@
AgnessGP
https://www.fiatforum.com/members-motors/268590-new-grande-punto-49.html
@
Ryaaan
https://www.fiatforum.com/members-motors/302660-ryans-red-grande-27.html
@
the rake
https://www.fiatforum.com/members-motors/294559-rakes-grande-15.html
All dropped on coilovers mate if you wanted to use lowering springs then Eibach's or H&R are the preferred choice and H&R will get you lower.
Kind Regards
Stephen