One of the best geartrains I found to live with was the old 2300 Sora. It needed to be set up on an absolute knife edge (not a problem if you know how to set up gears properly) or it could be clunky, but the thumb buttons for up changes were brilliant and much nicer to use when on the hoods, which is fantastic on real roads with real traffic and a real need to turn your head occasionally.
And my absolute favourite was the 10 speed Tiagra, I've got big hands (take note ladies

) so the longer lever throw felt much more natural to me. For all the fancy mech geometry and fluorine coated pivots, none of the higher ranked gear trains suited me so well,
Some depleted uranium and platinum Dura Ace looks absolitely lovely, but brings nothing to the party that helps me personally. You're just going to have to ride and ride and ride, get those miles under your belt on as many different bikes as you can and you'll soon figure out what it crap, what looks great, what costs a lot, and what actuslly gives a tangible benefit. The sweet spot is different for everyone, and time in the saddle is the only way you'll figure out where yours is.
And remember your grammar. What most people call a groupset is nothing of the sort - they mean a geartrain, and possibly brakes thrown in too. A groupset will include cables, skewers, seatpin, and even wheels, pedals and handlebars on some, so when people refer to a groupset they usually mean anything but. Stupid testers in glossy magazines are responsible for promulgating this rubbish.