after being adamant that hero stacking was balanceable and an important core mechanic (which i totally understand), blizzard eventually recognised that their perfect ideal had to be compromised because no hero limit was to the detriment of the game as a whole, and implemented 1 hero limit in competitive overwatch.
not saying blizzard don't have their own issues, but this impressed me a TON and is a perfect example of something valve would never do. valve is a) overly invested in their sunk costs into failed ventures b) money-hungry and blind to context and c) just plain bad at their job.
a) - the perfect example is obviously the overwatch parallel, refusing to implement class limits despite it being cemented as a much more important concept in tf2 than overwatch. in addition there's no weapon bans, no configs in mm, balance changes that follow their own ideas rather than the general consensus, and a general disconnect between them and the community/meta.
b) - lazy moneygrabbing updates that clutter the game and confuse everyone. despite the "hatconomy" already existing, they decided to basically copypaste in their successful csgo cosmetic tier system along with pick-up-able weapon skins on top of what we already had. needless to say, mixing two cosmetic systems in the same game was bewilderingly stupid. weird incomplete paradigms like hat tiering and statclock vs strange weapons confuse needlessly, and the glowing outline on dropped weapons + the ammo boxes on dead bodies add visual noise to an already cluttered game.
c) when valve take their own direction it's too often flawed or overcomplicated and their decisions aren't anchored in core principles or a respect for simplicity. for example the cow mangler and liberty launcher have been a billion different things when the cm5k could've been
- 5 rockets
- less damage
- a special altfire
and the ll could've been
- faster rockets
- less damage or 3 rockets
it's literally that simple, maybe it's not perfect and the values would be tweaked for balance but even so it's better than the trainwreck they have been under valve's direction.
games are more fun when a complex metagame develops out of a limited paradigm, so all these arbitrary tweaks end up more gimmicky than helpful. i personally even believe stickies should be balanced around being the same no matter where or when they're detonated (this might be less popular). ultimately, complex attributes only cloud the more interesting complexity that arises from the flow of basic 6v6 competitive tf2. make stuff intuitive, make it useful, make it work, and the gameplay - not the stats - will make the game interesting.
edit: quick note about the starcraft stuff: yeah they're technically complicated stats, but they make sense intuitively, so in terms of how a human processes it it's pretty simple. most of tf2's weapon stats aren't intuitive at all, aside from things like the huntsman (for which stats are hidden, but that's fine - see why?).