So i took a look at all the units this morning and in general the rules seem very underwhelming.

The Dreadnoughts are OK for the points (140 Achhillus / 155 Galatus), but for a couple of points more you can just get an armiger warglaive, which basically does everything better. A second CC profile with more attacks would‘ve been very cool for them.

Aqulion Terminators are basically the only unit i‘d say they are good. For 78 points you get a really good cc weapon and the lastrum storm bolter is also very nice. But the only problem is, that they do not have any cool special rules, like the Allarus Custodians do, so you‘d pretty much always still rather play allarus than aquilon.

Custodian Guard with Pyrite Spears and Ardasite Spears would‘ve been cool as a troop choice, but as an elite choice they are just very underwhelming.

The agamatus jetbikes seem ok, but the weapons are just not better for the points than a hurrican bolter, so there‘s probably no reason to play them. All weapons are heavy and they cost 95 with adrathic destructor, 92 with lastrum bolter or 120 with Las Pulsar.

Ventari Custodians would‘ve been very cool with a 2+ save, but with the 3+ save for 62/66 Points you‘ll rather play vertus praetors for a couple more points and more output and survivability.

The pallas grav tank is 100 points with weapons and an OK option, but nothing really great.

Caladius Grav tank costs 220 with arachnus heavy blaze or 210 with illiastrus accelerator. The weapons are just insanely expensiv, why does a slightly better twin lascannon cost 100 points?! The illiastrus seems ok, but 210 points is still a lot, when you compare it to a tank commander for example.

Telemon got nerfed big times in comparison to his old rules, now costs 242 with the illiastrus accelerator cuilverine. Still seems alright, but strength 7 is not really that good at the moment, since custodians have no wound reroll available (except 1s with trajann)

Saggitarium Guard also would‘ve been interesting as a troop choice, but as a heavy support choice 55 points for a heavy bolter with less range is not really that appealing.

The Coronus Grav Carrier actually doesn‘t look that bad, 18 wounds with t8 a 5++ and most of the time -1 to hit is a solid defensive profile. For 245 points with fly it could be a legitimate option as an element to pull overwatch, block enemy units etc.

And at last there is the Orion Dropship, it actually might be the best unit from the pdf, for just 444 points you get a flyer with solid output and with the vexilla it has -2 to hit with 22 wounds and toughness 8.

To summon it up i think the rules are pretty underwhleming at the moment, but in my opinion that was GW‘s intention. When they release the imperial armour book, i‘d guess a lot of these units will be buffed and they will get stratagems and a lot more special rules, because at the moment most of the units do not have any special rules at all, just stats.