I'm having trouble getting a sense for what might happen with Guard. In part, due to how bad Covid has been where I live I've had no opportunity to play 9th, I haven't been able to be truly involved with the game and how it's evolving, but I do long for the day where the Guard get to once more crush the enemies of the imperium under their mighty treads, and whose guns bring the sky itself falling upon its foes.
I have some theories, but first let's go through what observable facts we have right now affecting Guard:
- Huge cut to FW support:
- Elysians Legends'd, models cut
- DKoK extremely reduced, several models cut
- Most FW upgrades and unique gear Legends'd
- 3 limited edition Catachan models (Colonel, Sgt, Marbo)
- No new mainline models since the 6th edition splash of Scions/Taurox/Ogryn/Hydra/Commissar
- Handful of Made-to-Order metal model runs (Kasrkin, 3rd edition regiments, Vostroyans)
- Continued regimental rules support for legacy regiments
- slightly above average rules support across 8th:
- Specialist detachments
- Scion regiment rules expansion
- Considerable psychic awakening support (tank aces ho!)
I'm probably missing a few points which might belong here, but we can see a rough trend here of receiving very sub-par model support, possibly the fewest model releases of any mainline army since 5th edition, and if we factor in FW's posture, the most shrunk range of any faction, but have enjoyed fairly good rules support which respect's the Guard's diverse history - moreso than we have enjoyed since 4th edition.
GW clearly has no idea what to do with Guard as a model range, I suspect in no small part due to trademark-ability and difficulty in figuring out how to recapture the considerable revenue which goes to the numerous aftermarket Guard model makers (seriously, what other faction has whole studios who just make Imperial Guard alternate models?) in the same way Primaris took a chunk out of the Marine aftermarket industry. Mechanically, however, the Guard isn't doing too bad.
So what does this mean as a possible precedent for the future?
I think a range refresh is inevitable, but I find it hard to say whether or not it will be a good or bad thing for the faction. GW can't ignore the fact that there are other small businesses thriving off the neglect of this faction, but those same small businesses primarily cater to nostalgia (modernizing the old 3rd edition range, like Victoria Miniatures) or deliver historically and pop-culture inspired options (Mad Robot and Anvil Industries), neither of which are something GW, given its corporate anxiety over its own IP, would be likely to engage with.
They've already rebranded the faction with the moronic sounding Astra Militarum (which honestly probably hurt brand recognition in the long term, but that's another matter - we're in the Guard son), and while the few models they've released have all been Catachan, I'm not convinced they'll be the basis of a new range. Rambo is very much a product of the 80s, and Catachans landed with quite the whimper when they first came out (I don't think anyone has ever liked those models, and I have never seen a Catachan army in 15 years of playing on 3 continents), and they certainly aren't distinct enough to brand as their own IP.
Ergo, I expect something breaking with tradition - more akin to what was done in the Kasrkin/Stormtrooper to Scion transition. Could be good, like the High Elf to Lumineth in Age of Sigmar by drawing on tradition but making something distinct enough, or it could be generic and uninteresting like the Sigmarines. If we're damned lucky with the Emperor smiling upon us, I would wish for plastic Death Korps with an eye to modularity with GW selling upgrade kits to a few other regiments, but I'm also not crazy enough to think that'll happen. \
As for mechanics, Guard came through 8th pretty decently. I don't think we were ever a true powerhouse, but nor were we "alright, I was tabled turn 2, that's a new record" of late 7th edition. I think the old regiment rules will be with us for the long haul, as GW is happy to keep using them in their fluff, with Black Library and with the occasional Made to Order splash, which also means we're unlikely to see any dramatic changes to how guard units work.
Thus, in terms of "crunch," I think we'll likely stay as-is with only minor tweaks to costs, unit and weapon profiles with some mechanics to bring some of the poorly-working support units in line with other factions, like command squads and advisors, and maybe if GW is ambitious, something akin to the platoon rules or more specialized detachments (like Armoured, Mechanized, Artillery, Infantry detachments and so on) until such time the model refresh happens.
At the end of the day, the Guard "work" so until there's something which forces a more dramatic change, like a bunch of new models, I would expect more of the same, with the occasional attempt to make older concepts work again. GW keeps bringing back the specialized Guard detachments seemingly every edition under a new veneer, maybe this time they'll get it right?