[Formulajones]

Yes the weight of the valve train has a huge affect on spring pressures needed to control it.

On the beehive's, today there are many more options that work. Back when I was playing with them on LS engines there wasn't, so the go to solution then was a typical double spring swapped onto the LS engines. Beehive's have a few advantages though (smaller retainer being lighter is one of them) so if I could find a beehive spring package to work with a particular combo I was building today I'd go that direction.

Yes there are lighter valves than stock available. You could even get into hollow stem or sodium filled stuff (GM did this on some LS engines)
It just depends on how much money you want to spend. Personally I prefer to go with either titanium or tool steel retainers on all engine builds to lighten things up, and lighter valve assemblies when I can, even on a typical street engine build. Spring pressure will also be a result of how aggressive the lobe profile is. Even on a mild street engine build the valvetrain ends up being a somewhat spendy part of the build.