The Ultramarines are the best marines, so it makes sense that they would have Marines from other chapters working for them.
The daemon prince Ward is pleased with your remarks.
And yup, is either an old lady having her air colour running it's natural course, or the order that does so for tradition (the Sisters)
Now, I wonder, or better said, desire for a Space Marine Chapter, the game. A simulation/war game where you can play as a whole chapter. That's it, you control the 10 companies and the 100 battle brothers in each. But not just that. You also need to negotiate with the mechanicus for supplies, equipment and training for technomarines. You need to control the intake of possible recruits and the replenishment and training of new battle brothers. Also you would control the chapters fleet.
You need to respond to threats on your sector and/or help pleas from other systems and imperial institutions. Then you have to weight which resources you'll compromise if you choose to help. At this stage you could either simulate (auto resolve) or play the battle(s) yourself in a stile like that of dawn of war games. Also space battles should be played by you, assisting other imperial fleets while boardings are can be also either auto resolved or manually controlled and carried out. As you win battles you can get more equipment and perks by treaties with other imperial institutions.
Also except the occasional crusades that would drain your resources and inquisitor visits if there's anything suspicious. You should check for anything fishy and try to keep your gene-seed as pure as you can. Keep an eye on promotions and the leadership and what not.
Full customization and details for the squads and vehicles should be at order, from individual names and history of each battle brother, to vehicle weapon load out.
For all this you could either hand craft your own chapter, choose a randomly created one or pick a "historical" one to play either historical campaigns or sand box games with randomly/procedurally generated content. In the case you make one you can decide if it's fleet or planet based, the founding chapter it comes from, which sector it might be and so on....
What do you think? Should I email GW and Relic/SEGA?