I would house rule Spear into a finesse weapon too.
1. Why is Rapier the only d8 finesse weapon?
2. We need a two handed finesse weapon. Spear is the best candidate. Make it require Martial proficiency if it's "op" otherwise.
3. Who uses a Spear ever?
4. A High Elf Eldritch Knight with high dex who could throw the Spear and call it back would be really cool.
A two handed finesse weapon lol. You know what finesse means? Just as a reminder, finesse allows you to use dexterity instead of strength for damage on weapons which are very light. Go find a two handed weapon as light as a dagger or a rapier. Good luck with that.
The rapier is the only d8 damage weapon because it is the biggest of the finesse weapons.
Have you ever thrown a spear in your life? If you did, you must know strength is more involved than dexterity in the process.