Dune: shield lasgun explosion is very bad news for both parties. Side effect of the shield is that it repels fast moving attacks so even blades have to be slowed and duels become a real game of chess.
Combat knife would only have to have an insulated handle 🙂 but I do like the ida of an exotic material. It just seems odd to carry a knife unless you are in assault mode.
I am assuming combat armour requires a powered weapon to penetrate, either an energy beam, high powered slug (very bad news in confined, pressurized spaces), a small slapped-on shaped charge or thermite/melting attack, a laser or plasma cutter.
Could the tonfa have an integrated deployable knife or spear blade for more lethality without becoming unbelievably impractical? It is a nice weapon because it allows for parrying, gives a hard surface for punching and allows for a little extra reach and momentum without being unwieldy. It also allows for non-lethal combat to be escalated to lethal with a blade. Or maybe it integrates a one-shot armour-piercing round for last ditch defense against armour?