I remember AD&D very well. A big lone monster then didn't need special solo mechanics. They had higher hit dice, did more damage, had good saves, and that was plenty threatening.
Exactly! That's my point. Solo's should need "special" exemptions to the rules for the meta-game reason that they're solos. Rather, they should make sense as is, and perhaps due to their greater power happen to be appropriate for normal use.
Why? I have no problem with a solo or any other combat that ends fairly quick. I want the fight to be exciting game time and that means pressing the panic button. I would rather have 3 rounds of heart pounding action than 10 rounds and 2 real hours of grind.
I couldn't agree more! The way I see it, a solo encounter (barring exceptions) just doesn't work well for the same length as a normal encounter does. Making a "boss" monster is perhaps a way to run those "exceptional" solo encounters that somehow make sense over a period of 10 rounds, but in general, I'd rather have a combat that ends in 3 rounds of heart pounding action than 10 rounds of grind. A solo should be really, really dangerous, not so much invulnerable for reasons that make no sense in game.
There were mechanics for them. Before numbers bloat became the norm the attributes I outlined above were enough to make such a lone monster enough of a threat.
Stuff like hitpoints, defenses, attacks - they vary from monster to monster in a way that somewhat reflects the fantasy of the creature. The variety of abilities should suffice to define a monster. Yet solo's have been imbued with a variety of abilities that aren't reflected in their description or fluff whatsoever. An epic character would find it hard to get a constant +5 save bonus - yet a low-level humanoid solo has somehow achieved the same thing. The whole mechanical construction of a 4e solo is jarring, and should rarely exist.
Which brings me to the next thing you say...
Those types of encounters were iconic for setting/flavor not mechanics.
Which is as it should be. And
that's what's wrong with 4e solos. They're so focused on making the mechanics "work" that they're losing sight of the bigger picture - the flavor.
A PC Human is capable of far more than your typical villager. Why should that particular human be such a badass?
Probably because he's got magic gear, superior talents (attributes), superior training, superior motivation/bravery, etc. It's a fundamental assumption that these fantasy creatures can gain impossibly effective fighting skills and terribly powerful magic. The fact that all the monsters they encounter that happen to be alone happen to share a set of features (a template - the solo template) that no normal monster or PC could achieve through the usual means of gaining power, and that this template is so consistent across all creatures even when the fluff has no similarity whatsoever and ensures that these loners are handily resilient without actually being overpowering is like having a string of deus ex machina moments.
It's just too much nonsense, too much coincidence that gets repeated and repeated and repeated until the only possible response is to
not think about it and just roll the damn dice because the fantasy of it isn't internally consistent anyhow.
A typical solo encounter from the perspective of a PC:
Oh, a lonely goblin! He's not too hard to hit, can't be a risky opponent. Except he can attack lighting fast, striking 3 times when a normal goblin would once (weird, what a coincidence, just like that dragon last week). Oh, and somehow effect - no matter the type - just don't stick for long on him (weird, what a coincidence, just like that dragon last week). Hmm, taking long for him to go down, how can he survive all those sword cuts (weird, what a coincidence, just like that dragon last week)? Oops, he gets nastier and more dangerous when he's badly hurt - how uncommon (weird, what a coincidence, just like that dragon last week)!
Any sane PC would be forced to conclude:
It's a conspiracy - all those suspiciously similar and powerful loners - THEY'RE ALL POLYMORPHED DRAGONS - run!
Solo's just don't work well in 4e. Sure, you can fix the mechanics - but that's not helping, just making matters worse by encouraging their use: the real problem isn't the mechanics it's the lack of consistency with the rest of D&D. For creatures that are truly unique it's a template that could be used rarely; sparingly - like nails on chalkboard.