^Modding Combo Duration on the melee is a complete waste of a mod slot if you use Naramon focus.
Naramon is more than enough, and Primary/Secondary Arcanes can also provide combo duration. OP likely won't have access to those though. Swift Momentum is another free source of combo duration though.
Modding Corrosive on a Slash based melee is also a very bad build decision. Do toxin+cold for Viral. Straight up better than Corrosive.
Do you still need Life Strike? If not, then you can put the second elemental mod in that slot instead.
Sacrificial Steel is unnecessary with Blood Rush, so replace that with extra range. Primed Reach would be the best for extra range, but Spring-Loaded Blade is likely easier to acquire for you. The base Reach mod is rather weak, so might not really be worth the slot. If you don't have the Naramon Focus, you could put Combo duration in there for now.
After that, and ignoring straight upgrades, like Pressure Point -> Primed Pressure Point or Condition Overload, it looks good.
As for Excalibur:
-Your Armor+Health currently provide 2196 EHP, which you use 3 mods on, while Shields provide 1067, which you use 2 mods on. Depending on how much you rely on your shield regeneration, it may be worth it to use something else instead. Adaptation would be great, but probably not really obtainable for you right now.
-You'll probably want more Efficiency in order to be able to use your abilities more. Try getting non-flawed Streamline. Should be rather easy to get from Cetus bounties.
An alternative for Ability Efficiency is Fleeting Expertise, which adds +60% efficiency, but reduces Duration by 60%. Corrupted mods in general are great for specialized builds, so consider farming those.
