I like using Guardian for that reasoning, too. Many use it just to have to not worry about engineering two components. And you can under-class them, as they generally run a class higher in output. Well at least the PP.I see your points in Guardian PP & PD. Call me crazy but I actually like Guardian PP in explorer builds. It produces more energy and it's lighter than the G5 Armoured; it has more integrity than the standart and G5 overcharged ones. It produces more heat but who cares in an exploring ship.
Thing is, if G5 Armoured + Thermal Spread PP has enough power for your ship, it's generally the best for AX combat (or maybe for any combat?). If it doesn't, the Guardian PP may be a better choice because overcharged PP would lack the integrity and be too squishy.
I have a niche for Guardian PP (I used it in all of my ships including the AX ones lol) but I don't see any purpose of the PD. Sure, it boosts the PP but it's just meh. What if it's just enough for G5 Armoured PP to work on your ship? I don't know.
It has worse capacity and recharge rates compared to the Charge Enchanced + Super Conduits, it just has the integrity advantage but the main purpose of a PD in combat is the recharge rates. It just doesn't do its main job.
I used both Guardian PP & PD in my AX ships, I was too lazy to engineer the human ones, but they just weren't enough for a Medusa. It's just not fun when the old, regular human tech is better than the super new alien supertech hybrid.
What I would like from the guardian stuff is the set bonuses:
- Guardian PP boosts the HRP, MRP, SRP's
- Guardian PP & PD are more effective when combined together.
- Guardian PD has bonus recharge/damage/thermal efficency on guardian weapons. etc.