Progress has been made!
Firstly, I have acquired some more rocks from Spellcrow which now adorn the bases of pretty much everything in the army. I have also picked up some razorwire from Army Painter which I have attached to about half of them. I'm sure I'll post up some more group shots eventually but before that I'll give you the proof-of-concept with a few new minis.
Now, this is a (mostly) all-Gravis strike force and as such should probably include more than five Heavy Intercessors, so I present to you a second squad of them:

Yet again I've got Spellcrow tabards and the rest of the parts are almost exclusively from the Heavy Intercessor box, the only exceptions being theSergeant's head with bionic eye and bionic arm with bolt pistol, both of which came from the Eradicators box.
GW, in their infinite wisdom, have decided to reduce the number of Space Marine units in the soon-to-be-released codex and pre-empted this by putting afew models up for Last Chance to Buy. I completely understand the reasoning for this, the codex was very bloated with old units, but one model in particular stood out to me.
When I was just a lad, I owned a Land Speeder that my father built and painted up for me in Blood Angels red. I loved that model but sadly it hasn't been in my possession for about two decades. When I saw that it was going I immediately knew that I had to get one.
I actually ended up getting two but I've only built this one so far.



As you can see, it isn't entirely stock. The pilots looked very small and I wanted them to at least somewhat fit with the Gravis marines. I started by giving them Heavy Intercessor helmets which looked rather silly given the scale of the old Firstborn crew so, to try to make them fit a little better, I acquired some Mk III Space Marine shoulder pads. Some pouches and a holster helped to hide the fact that these boys have definitely skipped leg day and the addition of purity seals draws the eye away whilst also fitting in with the rest of the army.
The gaping holes in the sides are where I can attach the Typhoon missile launchers. I've got magnets inside that will just about hold it all together. A much stronger magnet under the nose can convert the Land Speeder into a Tornado (as they're a Salamanders successor chapter I opted to just build up the Heavy Flamer assembly, who needs Assault Cannons).
Land Speeders are technically Legends units now (or at least, they will be in a couple of weeks when the Index is replaced witha shiny new Codex) but I don't play in tournaments these days and I'm sure my friends won't mind.
Coming soon: Some more older models that will probably be Legends by the time I upload them here.