If you’re waiting on a cape to level Grimm, then it looks like you’re short on the mats to level 5* heroes (Congrats on your pull, btw!).
I agree with @FearFury to focus on your 4* heroes first. Having a nice roster of 4* heroes will get you further in the game (map levels, quests, events, etc.) than partially leveled 5* heroes. The further you progress, the more opportunities for mats. Hold on to your 5* heroes, but don’t level them until you are close to getting all the mats. Focus on your 4s for now.
By the time you have the mats to level a blue, you may have more choices than Richard or Vela. But if you’re still in the same spot, then I would level Vela. Richard makes an ok tank. If you’re in an alliance that runs blue tanks for wars, then he’s an option. Otherwise, I don’t find him amazing. Vela has her weaknesses, but is overall a better hero IMO.