Striker’s Ultimate stuns / staggers bosses and mini-bosses. So going up to one with Breaker Mace, is safer since they won’t be able to hit back. This lets them 1 vs 1 duel with Carriers, Snatchers, Matriarch and Wardens.
If Blademaster uses Electro Blade Ultimate on bosses, they would fight back since they aren’t getting stunned or staggered. So using Electro Blade Ultimate on Warden, would cause the Warden to swing their Breaker Mace back, downing or killing Blademaster. An alternative would be to stun Warden would Flashbang then use Ultimate. Going up to Snatcher, Carrier or Matriarch with Electro Blade would probably not end well.
Outside of venom against melee enemies like Juvies and Rejects, Striker would probably survive better with Stim on each melee hit, plus the bonus GSD Legendary card explosions on melee kill, which has very short point blank range anyway so not that great.