Sure then feel free to ignore the Steel/Klaus Unit Set if you want. I personally agree with you on the steel weapons as will only really benefit ranged classes as they don't have to rush into danger like Melee classes, that's a given.
The units can be mixed and matched so you really don't have to go for the full set unless you want to. If anything, pick the Klaus unit you want the stats for if you already have other 13 star units.
Shiva's, it would likely take me another three months just to buy one unit because I don't have time to obsessively grind Divide. Building Klauz units are for people without responsibilities who can play 16 hours a day
I also have responsibilities so I am not sure what you're on about. No need to "obsessively" farm the Materials for Units. You just need to pace yourself and be patient. The only real way this will be difficult is if you're the type of person who can't wait to obtain what they want. Also, we have received Triggers for many different Triggers; I won't be surprise if we get a Trigger for Final Lament (which then you can run on your own time as there will be people who need the units).
People seem to think because NG is around the corner that all this upgrading in base PSO2 is pointless. I can say it'll definitely give you something to do between content release for NG as well as maint (if you don't want to play something else).
If you don't think you'll find yourself coming back to Base PSO2 after NG release then yeah you can ignore the "endgame" stuff (Steel series is not endgame imo). Though I will mention I highly doubt NG is gonna have months of content right away if they continue the slow release of content like they have been doing with base PSO2.