I have enjoyed my forays into Lion Rampant using some old SAGA 28mm models. However having played Warmaster [10mm] and Hail Caesar!/Black Powder in [6mm] I've grown to love the smaller scales and choice.
I decided I'd try looking at playing Lion Rampant in 10mm as it might fit in with Warmaster and there are resources from Pendraken and we might go the Warbands route too, more games for a model size = less paint more play!
Planning
1) Unit size: Mounted is 6 horse per unit, Foot is 12 men [ Except, Men at arms/Bidowers only 6]
2) As a mounted man takes up the same space as two men then base a unit of 6 horse on same base size as a unit of 12 men.
3) Allow some flexibility of formation, but rather than have the models individually based, base them in smaller groups.
4) As a unit's attacks are reduced to half when half sized then break units up into at least two bases.
Thus I'd suggest
3 horse per base
6 foot per base [3 men at arms/bidowers per base]
Base size................... I happened to get 40 x 40 out of box [hand of fate]
So
three horse on a 40 x 40 base,
Six men on a 40 x 40 base -
Both effectively an 80 x 40 unit
Men at arms/Bidowers These units are half sized so I'd suggest basing 3 men on a 40 x 20 base
Effectively an 80 x 20 or 40 x 40 unit
So from left to right, Men at Arms, Mounted Men at Arms, Foot Yeomen with bow and Bidowers

At this point jaw drops as I look at models
Doh!
Warmaster

So if you all fancy playing a different game on the odd occasion get your warmaster models out and play Lion Rampant.
Or if you fancy the new Warbands game you can buy this from Pendraken
here for 50p each, simple conversion for my Lion Rampant or Warmaster, if required blanks can be slotted in where the number of models ain't enough, 2 of 20x20 for example to centre a rear rank of one foot.
100x50mm tray with a 80x40mm internal space, able to hold four 40x20mm bases. (40x20mm bases sold separately)

and get

BTW I don't work for Leon, just love his models.