Gotta say the SAV units are simultaneously surprising and boring. Here're my thoughts:
Fast: Energy Cannons are tied with Eels and Gliders to become the fastest units in the game without Rapid Deployment. They'll be solid first-strike units for the continent map in particular and a strict upgrade over Sentinels in general, unlike Hover Hammers which are generally worse (but not always!) because of their attack range. Flying loses its defensive utility against the Power Dragon but it'll still be useful for the early rounds of GE and a lot of the continent map where players are still facing SAAB units.
Heavy: This one might be the biggest surprise to me. The Steel Fist has an initiative of 20, making it the fastest heavy unit since the Battle Fortress. It's realistically only going to be facing SAAB and SAV units though, so this increase over the Shredder means it only moves faster than they do and ties with B.E.L.T.s. I guess this could be useful by itself, but Steel Wardens already work just fine against both of these and you'd most likely be using something else in this situation anyway. So ultimately...I guess they'll be annoying for players to fight against due to Reactive Armor, even though it's only 4 instead of 3. Like I said, this unit surprised me!
Light: For the first time since the Manta, we have a light unit with a range higher than 1! I'm sure many players will be happy with this, but I'm not really seeing a niche for them to fill along with it. Why not just use Energy Cannons instead? Better range and more mobile. Stealth does end up being more useful than Flying in this age, but against what? They're still pretty short-range and they're the slowest units in the age, meaning everything else will have the chance to fire on them before they can hide. At least they continue to be as mobile as light units have ever been so it won't be too hard for them to make it to the broken ground.
Artillery: Ahhh, the Power Dragon. Slot it in with 7 rogues (or 2+6 rogues if you're nervous) and go to town with your auto battles. What's gonna stop you? They may not be the 'strongest' unit statistically like Rail Guns were in the Future, but they make up for it by not having Recharge. These monsters are gonna do just fine throughout this age. They have the same initiative as Nail Storms as well, so if the Nail Storms are outnumbered the Dragons will be able to fire on them before they start getting hit back. If Energy Cannons are the go-to unit for the continent map, these are the unit for everything else where you can get away with using Rogues.
Ranged: Ghost Blasters are more or less a straight upgrade over Nail Storms. Their one big weakness is that they're terrible first-strike units. Anyone who's fought manually with Nail Storms knows they can't always reach the other side on their first turn. Now imagine if Nail Storms had one less attack range in battle. That's the Ghost Blaster! They won't be able to do much on their first turn, so if that's something that matters to you then stick with Nail Storms. 30 initiative does mean they move before Nail Storms though!
Champion: Wow, those stats! His mobility is still terrible, but he's almost got the defense (1200!) to make up for it. But with how the Champion's stats have been growing the past few ages relative to the other units, I think this guy's finally coming back around after falling off hard in Arctic Future. With the Power Dragon around, this is probably the strongest heavy unit in the game right now! For better or worse...
Final thoughts on SAV's military offerings are that they're...fine. This has a lot to do with SAAB being generally underwhelming though, making it easy for this new stuff to look great. I also fear that battling is starting to stagnate, though. Ever since the addition of AR Targeting (since renamed to Keen Eye), this has limited units to just one other ability. This wouldn't be bad by itself, but it seems that new abilities have also stopped coming and we've been seeing the same stuff for several ages now and it's usually the weaker abilities as well. Stuff like Contact! on units with low or 1 range, Blast, Heat, even stealth isn't really that amazing these days. What happened to innovating? Introducing new abilities to shake things up? Or maybe even making another big change to the battlefield like was done starting with Progressive? I guess these things could all end up falling flat and just looking like change for the sake of it, but I want more from a new age than just seeing different graphics on the screen!