I have based up my new MKIII and MKIV tactical squads (plus some hangers-on) for my 6mm Death Guard so thought I would post some work in progress pictures.
Here you can see the tactical stands on the left (14 stands), 6 character stands and two command stands in the front, and three tactical support stands (two flamer and one melta) and three heavy support stands (two missile launcher and one heavy bolter) on the right. I mixed the MKIII and MKIV armour types up for a bit of variety. I also put three models per stand, to help represent how resilient the Death Guard are (at least in my mind anyway!).
The bases are steel washers (33mm "mud guard" washers from a hardware shop) with the models super glued onto them. I then glued washed sand on using pva glue. You can also see some models with chainswords mixed in with the bolter marines. Chainswords are valid upgrades for tactical squads in the 28mm game, so I was comfortable putting some assault marines without jump packs in with my tactical stands to represent this.
Here you can see some of the characters: left to right they are a jump pack champion (with a power fist), a librarian and jump pack chaplain. They have 3mm magnets glued to the bottom of the figure, and I made up 25mm steel washer bases for them to sit on. In games of Epic Armageddon (where characters are taken as upgrades for other units) I can take the model off the base and put it on whatever stand is being upgraded. In Net Epic and Epic 40k games these characters can use these 25mm bases. I also may experiment with using 6mm models for games of Warhammer 40,000 (and 30,000) some day, in which case these bases will do the job.
Still to come are the rhinos for all of these, plus I will probably do some more support stands to get them up to a Net Epic usable 6 stands of each. That will also allow me to take two havoc upgrades (which are three stands each) in Plague Marine Epic Armageddon armies.
So a little progress, and a fair bit of work trying to keep my options open, but still a long way to go.