3145 Wolves had 75 Clusters, but the Empire has to ward against Homies, which at last count numbered 4 Clans. Both sides have access to Society tech, but so far the Empire hasn't even bulked up their Touman with enough regular tech units. Pre-WoR combined strength of these 4 Homie Clans would be 150+ Clusters, and they still have WarShips outnumbering the Empire's 3. So yes, just for adequate defense(assuming Homies get to rebuild and expand), the Empire needs 70+ to minimum 150 Clusters, not counting expansion of the Imperial Navy.
Empire is increasing it's Touman, this was confirmed
And 42+ Scorpion clusters are not the only thing they have, Garrison Caste is there too and while troops may not be the best and are vehicle centric there is whole lotta of them and are armed with IIC mechs and omni-vehicles like Epona
So while Empire Touman may be at 42+ the overall Imperio Militar should be at that number 70 or more which you mentioned only caveat being that Garrison PGCs are stationary and it's only Touman which can engage in offensive operations
As for Society tech there's are reason nobody is concerned with it: it's dezgra beyond belief
Only Stone Lions are allowed to experiment with some elements of it and only under strict supervison of Star Adders and Clan Council
Some of it would make Blakists go "nah dude, I'll pass" (remember Feralize for example?)
That stuff won't be making any big splashes not that it was packing much punch to begin with, it was just geared to exploit enemy's adherence to zellbringen and it didn't even succeed at that properly (plus Scorpions ditched zellbringen outside their Clan trials anyway)
In universe I doubt that Scorpions are completely in the dark about general situation in the Clan Homeworlds (Clan Watch is on the job) otherwise they would have kept war with Hansa on the back burner and stay focused on them
CGL will not be repeating Clan Invasion storyline, they said as much but something else could be in the cards (I did post my humble suggestion on Star Adder tread if anyone is curious)
And before anything big happens CGL will flesh out Home Clans to make them more interesting and create even footing with enemies like they did with Ghost Bears and Combine in Dominions Divided