Personally I tend to run solo and prefer staying at range so I run a destro/resto build with 5 Kagrenac, 3 Willpower, 2 Torug, and 1 Kena which works quite nicely, but I still haven't decided whether I prefer 5L 2H or 5L 1H 1M,. In my opinion the added regen and penetration from light armour is way more useful than the mitigation heavy armour provides. I'd worry about being too squishy running all light and the only time I've ever considered running 5 heavy is if I were to run Imperial physique. Which setup you choose largely depends on how you're wanting to play tbh, but if you want to tank in a group then you should run 5 heavy.

Going from say divined/infused to all impen is like night and day.

If your running impen it's a lot different.

I run 5l/2h on my magplar with all impen and I'm tanky enough

@AGrz5585 that's exactly what I was running, same magnus & julianos set up but with infused and divines and all light. when you say running impen is different do you mean better or worse?

You will need to adjust your playstyle when running heavy armor. Though your mitigation is higher and your shadow barrier is constantly up you lose penetration, magicka sustain and spell critical.

You have to rely on heavy staff attacks to recharge your magicka which renders dual wield more or less useless as you will definitely need the additional sustain and penetration from destro staff and the reduced cost and ultimately generation of strife weaving.

Another issue is the loss of crit. Though with impen meta the use of offensive crit is not as great as it used to be, magblades are dependent on the constant crit of HoTs, especially when NOT able to cloak.

The problem of magicka sustain comes into play whenever you are not getting hit to proc heavy armor passive. So cloaking away or shield spam will be a problem when your magicka was already drained by active fighting. Try running the annulment morph that gives back magicka together with siphoning attacks and MA/Strife weaving.

You might want to run tavas 5pc with Mirage to enable a constant veil of blades/soul tether/devouring swarm for additional annoyance.

Light. At least 5-1-1 if you want to benefit from undaunted but 7 lights makes sense since it increases dampen strength by 12% which is really nice. On top of 6% reduce cost, 8% regen etc.And as you said because of dropped sets you dont always have the choice.

I always run 2H/5L on my casters. I do the Legs and Chest in Heavy and mixing in light for everything else almost always works for any Racial Style, other than perhaps Redgaurd Heavy, at least at lower levels (subCP100 I guess now). As that Heavy Chest piece pretty much requires the Heavy Shoulders to look right.

Heavy if you want to die with no resources and light if you want to die with full resources

I run a unique build different from everyone else: (everything golden, all impen except sash)
5 heavy 2 light, tristat food, atro mundus, vamp

head - elf bane
pants - elf bane - prismatic enchant
chest - elf bane - prismatic enchant
boots - elf bane
shoulder - kena
gloves - seducer
waist - worm cult
neck - worm cult (sp dmg enchant)
ring1 - worm cult (sp dmg enchant)
ring2 - worm cult (sp dmg enchant)
sword1 - worm cult - (sharpened)
sword2 - seducer - (sharpened)
resto staff - worm cult (defending)

bar1 - sap, lotus fan, impale, concealed, inner light

bar2 - cloak, immovable brute, swallow soul, resto bubble, prolonged suffering (morph of agony)

enjoy,
-Kai

Potions won't account for 20% reduce cost to break free, try going up against a magicka dk that is spamming petrify on you.

I swap between typical spell damage + sp crit pots for increased burst & tri-pots for all stat recovery depending on the situation.
Immovable pots just aren't worth it because I have immovable. If I remove immovable it would be for magicka harness or siphoning attacks depending on who I'm fighting. ( obviously magicka harness for sorcs )