It's been awhile since we've had one of these threads, how cool! I'm not ready to post mine yet, but I'm happy to give some recommendations.
>>10651662
I think your ideas are solid. Robin or Invincible would be my picks for you. To give some more, I think Richter from Castlevania (the design that appears in Smash) or Amadeus Cho (Marvel) would fit your tastes.
>>10651747
All of your ideas would be great projects for beginner to intermediate sewing. From them, I think Scout's mom fits you the most -- they're all good ideas though. To give some more, I'd say that you could pull off Tanjiro (Demon Slayer), Ray (Promised Neverland), Kaneki Ken (Tokyo Ghoul), any one of the School Live girls, or Ganta (Deadman Wonderland). Typically boys who are pre-puberty or just reaching it (like Shinji) are the easiest for those starting to crossplay -- this is great for you because it means most main characters of shounen series are ripe for the picking.