One division that might be relevant is space-worthiness. While I still feel that most aero-units are the auspice of the Navy, an argument could be used that, if the flier isn't space-capable, if it is stuck on that one planet without the Navy's voidships to carry it, then some leeway could be granted the Guard. There are few worlds that the Imperium genuinely cares about, and they want to control them all, so if the Guard can benefit from some Valkyries, and hold superiority over Orks, Nids, and what have you, so long as that power can't extend beyond that planet, all power to them. The Army had to go because they had voidships, regiments, armor, artillery, and the ability to topple a sector, or more. Even the strongest Guard unit, limited to a single world or system, is still nothing to worry about. If they had a light cruiser, Space Marines, Storm Troopers, and armor, then we'd have to care.

I largely agree with this.

Sometimes, that's why I wish that the Space Marines were a bit more integrated, and a bit less written-by-fanboys independent (no disrespect).

As far as I can tell, space marines are purely written by fan boys*. All disrespect intended.

* and probably professional authors with homes, car and families to make payments on. They were ... not quite young anymore, and needed the money.

I don't think it's really all fanboy. SM operate on a very similar model to the US Marines today (Albeit on Uber steroids!). The Astartes are a completely self contained force capable of mounting the initial assault against any target and even ending some brushfire wars before they really begin due to their ability to surgically remove core elements of an enemy force before they can organize. In a similar manner the US marines have their own dedicated naval vessels (Although operated by the navy a Wasp class LHD could probably make a good analogy for a current era battlebarge!), Naval support, Air forces (Which are operated by Marines!) and even special forces. Like the Space marines the key is the Initial assault. Once the conflict spreads out into a larger land war the Marines need the Army which is more geared to that kind of large scale (Typically more mechanized) warfare. The Marines and the Army rely on the Navy and Air force (respectively) for more strategic level strikes. You can see this as well in 40k. There is no doubt that a single Space marine is a LOT more effective than an IG Infantryman (Though the difference is not nearly as drastic the same could be said for the difference between a Marine assault infantryman and an Army Light infantryman) once the battle become mechanized it quickly goes the other way! There is no way that the Predator tank of the SM holds a candle to the mighty Leman Russ main battle tank! The Rhino is a clunky tracked box compared to the faster and much more heavily armed Chimera! Even the mighty Space Marine Land raider is dwarfed by the Behemoth Baneblades of the IG!

The point here is that the Space marines fill a different role than the IG. They are rapid response shock troops whereas the IG are you conventional fighting army. You need both if you're going to fight a major war!

It is kind of odd that the Marines have a worse standard APC than the Guard.

It is kind of odd that the Marines have a worse standard APC than the Guard.

TT it's 11/11/10 vs 12/10/10

Nothing really new there.

Oh, and chimeras get a heavy weapon, rhinos don't.

and 5 firing points instead of 2 for the rhino

most importantly a chimera can field an autocannon making it a good support against other apcs

Well Rhinos aka Razorbacks can field a lascannon.

And the Space Marines can slightly more afford to get out. A Rhino, in my eyes, is to get the Space Marines to a place, where they can assault, and then they're out, or get them to an objective, to hold, and then they're out. Once they are out, and where they wanted to be, the Rhino is useless, so it can go boom. As many Space Marines might choose to drop pod in, and that just sits there. IG don't drive to assaults, so their vehicle needs to survive to back them up, and it does pretty well, too.