I'll be an iconoclast here:
1. .22 LR. Yes. The Model 70 ought to be issued in a micro-action, chambered for .22 LR, .22 WMR, .17 HMR and .22 Hornet.
2. .223 Rem. This would be a mini-action, able to handle cartridges in the .223 to .22-250 range.
3. .260 Rem, but with a fast twist barrel, identical to the 6.5X55 twist. This short action would also handle 7mm-08 and and other .308-based cartridges.
4. .30-06. The same action would also handle .300 WM, of course.
5. A true magnum action for cartridges ranging from 7mm Rem Mag to .375 H&H to .458 Lott.