The FG42 was a sensational gamble.
There are several reasons I think it was an outstanding weapon for it's era.
It was a select fire package that weighed the same, and was as short as or shorter than most intermediary round assault weapons, but the FG42 fired the full power 7.92mm round.
It fed from a 20 round box mag, but the mag was horizontal, so did not affect your prone silhouette height. Some have said this weight could throw off your aim, they are correct that it may lopside the rifle slightly if you limp wrist it, as if you were an eleven year old girl, and even then, it shouldn't throw off your aim.
It fired from the closed bolt in semi for greater accuracy, but open bolt when fully automatic was engaged, so less chance of a cook off.
It had an integral bipod and bayonet, full automatic prone from bipod position was very steady.
It had an advanced muzzle brake, to deal with the hi power cartridge's recoil.
It also had a reciprocating stock.
The sights are fold away, much like current combat assault weapons.
Spectacularly simple to disassemble and clean.
I feel the FG42 was a magnificent experiment, years ahead of it's time, that took a very typically Luftwaffe, hyper pragmatic approach to the assessment and design of a battlefield weapon.
Instead of issuing your troop intermediary round assault weapons and one or two GPMGs, you had the option of having every man carry a form of hybrid intermediary GPMG.
I think in time they would have designed a way for the FG to accept MG42 belts as well as mags, with a slightly more robust or quick change barrel.
(no more rifles, smgs, assault weapons or gpmgs)
I think the weapon would have become a major success, if certain political and military decisions hadn't lessened the importance of the FJ trooper in general.
The FG was clearly a source of inspiration for the M60 gmpg in later years.