For the Hundred Years War, I'd start with the
Accurate/Revell French knights and English foot
soldiers. The Italeri sets mix well with these and
are very good as well.
After that, the choices become poorer. There
are Strelets set of Henry V's army and Joan of Arc's
army (actually these two never fought). The mounted
poses in these sets are very poor in my opinion,
(neither side had archers who foughts from horse-
back). The foot poses are better, though a little
clunky compared to the Accurate or Italeri figures.
On the plus side, the Henry V set has a lot of archers, (who made up the bulk of the English armies),
though some of them are in fairly strange postures.
The Zevezda French knights set is very nice with
a good number of figures (19) for a cavalry set. Un-
fortunately 6 of the 19 figures are using either a
crossbow or firearm - neither of which were fired from
horseback. But the other figures are very nice. They
would only be appropriate for the latter part of the
war since their armor if very advanced.
The miniart figures are also a bit clunky and
I haven't bought any of them. The French and Burgundian mounted knights are very poor quality.
The German knights are better - probably their best
quality set. The Burgundian foot figures have a lot
of archers and crossbowmen and some pretty good foot
figures. I hope this helps.