Harald Hardrada [w'Old Glory 25mm fig for comparison]
Combo Standard-bearer and Horn Blower
Command Pack Warlord and a Berserker
Two more berserkers - one on right looks especially berserk!
These guys are really ulfhednar, wolf-pelt wearers
The rest of the crew p.1
Shield variety in the packs
There's two major types of variation I try to represent on my dark ages figures. The first is the general variety of colors and items that research reveals. So for Vikings the most popular tunic colors are supposed to be red, blue, and "leaf green". Four to five other colors are mentioned. The second is what I think of as individuality. These are the little changes in skin tones, personal items and such that mark these people as individuals who dress with what they have for war and not in some sort of "Viking uniform".
With the row of figures laid out on the sticks, I use the columns to plan and track variations. In the below example, I've four different base coats for flesh, one to each row.
I'll do similar things with each stage of the painting, so 1/4 of the group will have red, blue, or "leaf green", while the last 1/4 will each have a unique colored tunic. Organizing this way helps me to plan variety quickly. Using diagonal and other patterns to paint belts, shoes, etc, will give lots of variations and when the figures are on the table they'll look varied yet similar enough in the painting tones to all be from the same area / tribe / etc.
After I've painted all the basics, I hit the little touches of individuality. I try to characterize anyone who's interesting in pose or weapon, and give even the shieldwall types at least one thing to mark them; ornament, hair, shield color, something unique. This reminds us that they're all individuals gathered to fight, not highly trained uniform types like today. This stage can take the longest but is usually the most fun for me. Special characters like generals and warlords will get a bunch of time spend on them.
I've done this with all sorts of dark age figures, from Goths to Saxons to Welsh, and it's worked very well for me.