Centerfire cartridges using smokeless powder is 125+ year old technology. Don't get too wrapped up in how long something has been on the market, in judging its effectiveness and quality.
One of the best rifle cartridge hunting bullets on the market uses cup-and-core "technology" first introduced in 1877.
Hydra-Shoks are decent. Don't worry about them, as long as they function properly in your firearms.
3. This is what Ruger has to say:
"Note on +P Ammunition: Although the RUGER® LC9 is capable of
functioning with 9mm +P ammunition, a steady diet of +P ammunition will
shorten the endurance life of the RUGER® LC9. You should never shoot 9mm
+P+ ammunition in your RUGER® LC9. There are no SAAMI or CIP pressure
limits on 9mm +P+ and use of this ammunition could result in serious injury.
" [emphasis mine]
4. If your firearm can handle it, and you think the extra velocity (if any) will help, then feel free to use +P ammo. In general, it doesn't matter whether you use +P ammo or 'standard pressure' ammo. (I use quotation marks for "+P" because many of the loads actually being sold as "+P" aren't actually operating with increased pressure - which is what +P stands for "plus pressure". Most of the loads are pure marketing, and hardly, if at all, better than 'standard grade' offerings.) Just be sure to thoroughly test the ammo before deciding to trust your life to it.
5. I ran Hydra-Shoks in my 9mm until they were in short supply for quite some time. I tried a few other options (including the miserably-performing Hornady CD ammo), and ended up settling on Speer 115 gr GDHP +P. I prefer a 147 gr bullet, and my pistol usually runs better with heavy projectiles; but the 115 gr load was 100% reliable and cheaper than the other options. It's also a good terminal performance option. So that's what I stocked up on...
One thing that has always treated me well, but I can almost never find (or I can't find it at a good price) is the Winchester Ranger SXT line of ammo. It is essentially a "Black Talon" without the 'evil' Lubalox surface treatment on the bullet. The have always run perfectly for me, and the bullet does a great job. But, I can never find what I want, when I'm in the market.
I need a new signature. This one sucks.