As another samurai I generally mix it up a fair bit. Sometimes it's light armour, yumi, and katana or dadao, other times it's heavy armour and nodachi. I find both styles fun, and it's nice to be able to switch around depending on mood and needs.
If enemy side is cav-heavy I might for example go for the bow instead, to dehorse a few, while sometimes it's nice to just slug it out in melee with the nodachi and a it-takes-many-arrows-to-kill-me suit of armour.
1.7mil more to my first retirement, and for that I'm probably going for polearms and archery instead, or even 100% polearms, just to go with the long hafted blade (which is more 'samurai' than running around with a sword is, even though I like the nodachi).
@Deutschritter: Longbow is useless because it uses two slots. Samurai builds can only afford 1-slot bows due to 2-slot melee weapons (nodachi, long hafted blade, spears, katana), and the yumi is the only samurai-bow there is anyway.