SP Excalibur Umbra.

Hi, so, i've loved Excal since i started playing, i played him for at least half of the SC, but i've come to realize, that Excal isn't particularly good at later stages of the game, which sucks, 'cause as i said, i really like him.

So the question would be, is there a good, or multiple good SP viable Excalibur Umbra builds? And if possible, don't just tell me the build, but how should i build him, so if i want to try different stuff i don't have to waste time trying things that are plain useless.

Feel free to be as detailed as you want, be it very, or barely. Thanks in advance.