100% seadra

Kingdra isn't a Pokemon I'd waste 200K stardust on... If it was Dragonite maybe.. just maybe..

In my view this game is about long term projects and I'm a perfectionist. I would evolved and see what moves it gets and then slowly power it up if I like the moves. I have a 99% seadra but don't have enough candy or the item yet.

As sad as it is to let go a 100IV, low CP or Lvl 1 mon, I have done it a few times. Even if moveset turns out to be good, too much stardust to level up to 30 and especially 39. And to gamble 100 candies (mons with 2 evolutions) hoping for a good moveset then have to power up... I don't know, just not worth it. Keep it as trophy at the most

Evolve him as trophy for being hard worker... Kingdra is not worth to power up... Just evolve him for dex entry...

Definitely keep it, but I wouldn't invest in it unless the meta changed dramatically.

Remember you can always get dust and candies with patience, always, and horsea isnt hard to find, but the IV wont change ever, 100% iv pokemons are hard to find and nobody knows if a moveset change will come and currently isnt a meta guy, i bet it can be powered up enough to be prestiger and leave it there as trophy or future wise use