Ah, nuts. i didn't read that top text properly.
I didn't feel i could really comment on the list because i think you already own the models and i wouldn't want to recommend not using the stuff you already have.
especially after that goof i just made.
i think myrmidons are great (bought three squads of each) but i never finished the secutors. the destructors had a fun 'heavy weapons squad' kind of appeal that i felt happy taking mixed weapon sets but the secutors feel a little too single-purpose; the phased plasma fusil is their best trick but mixing them with the other options feels flawed rather than tricky. they really suffer in comparison for not having preferred enemy (everything)
So my typical loadout for 3 destructors was 2 volkites and a photon thruster. if i had a second unit out i'd have two irradiation engines and a volkite culverin or two photon thrusters and a volkite culverin
That said, a unit of two volkiites and two photon thrusters had great punch long range while still not being the primary target until they take a big scalp
I'd put the secutors in the triaros but the adsecularis feel a little weak for footslogging to me (no RoPT or RA upgrades)
I mean, they are pretty much hangars for participation medals and
maybe plate carriers, but against most opposing forces the thralls are bad fodder in that setup because it's fairly easy to trigger total unit death by
Ld checks off the board or sweeping advance - admittedly, that can be fun if you have 6 units of them and a Lachrimallus Magos Prime
good times.
Apart from that one game against eldar.
Okay, so magos loadout varies depending on base type
Calleb Decima - everything. obviously no 'decima invictus' upgrade when playing pre-heresy or mid-heresy
Archmagos Reductor - macchinator array, abeyant, cyber familiar, Protectiva, swap lucifex for photon gauntlet, master-crafted photon thruster, cyber occularis, djinn skein, augury scanner
Archmagos Malagra - jetpack, abeyant, four cyber-occularis, cyber familiar, Protectiva, paragon blade, master-crafted paragon blade, rad grenades, djinn skein
Magos Lachrimallus - as the archmagos reductor; basicly the backfeild artilleryman and fixer-upper.
Magos Ordinator - as the archmagos reductor but with four cyber occularis
Magos Dominus - macchinator array, abeyant, cyber familiar, swap maglite for archeotek pistol, master crafted photon thruster, augury scanner
so i have them working in the backfeild like a smart artillery peice usually; i tend to kamikaze Calleb Decima in an intresting vehicle and the Archmagos Malagra provides assured deep-strike after deploying (it works as soon as it's put onto the table so i deploy them first) and the magos dominus is a straight up Thanatar shepherd.
so, quite heavily tooled up. i don't like giving away slay the warlord.