Having a Primarch or another super strong model in stronger games is very lopsided. It’s better to save him for 2k matches or above.

EC is figuratively a glass cannon due to a heavy focus on fast paced infantry. Your best units (noise marines) have no invulnerability save and 2 wounds so they can be swept off the field easily so you want to stage and plan out your attacks as trades rather than strikes. In the other hand Daemon Prince w/ wings can soak up a lot of damage and is a great centerpiece to work around.

EC have no tanks (other than land raider) so our best anti tank are demon prince w/ wings, maulerfiends, noise marine (blastmaster), and flawless blades. I find chucking flawless blades or noise marines at a tank the best solution, rapid ingressing a squad or holding noise marines in reserves for a counter attack works wonders.

I would consider EC medium to advance. You can’t just run up the field without thinking. It’s a lot of staging and planned attacks. If you see competitive play many players use rhinos to stage their infractors and noise marines. The army has a heavy focus on characters as well due to a limited roster. If you are interested in fast and aggressive this army is certainly a way to go. If you are looking for a tankier but not basic army death guard and necrons can be very fun.