If you want what I think the lightest touch is that will produce a useful scout:
Reconnaissance (old): Gains XP from revealing Tiles, up to 100 XP.
Reconnaissance (New proposed): Gains XP from revealing tiles, +1 for ending the turn for every enemy in sight (max 5xp), in enemy lands and 5 from pillaging tiles. No max.
Unit changes:
Scout:
- Penalty to attacking non-barbarians, -33%.
- 3 sight base
- +4 CS at iron working and steel working. (They'll never attack well, but they can actually defend this way. This also keeps them useful without being OP at any point, or requiring more units. Explorer doesn't get these bonuses, but could be looked at if it's weak.
- If possible, production/gold cost increases at iron and steel.
Explorer:
- Sight 3 base
- Embark Oceans immediately.
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The purposes are the following:
Reconnaissance changes are needed to allow building more than 2 scouts. You just can't level them up otherwise.
CS scaling to avoid being OP or UP at any point.
Penalty attacking non-barbs to avoid messing with early game barb balance (good as is) and avoid being potentially too good in wars.
I'd like to see the promotion tree reworked, but it doesn't NEED to be.
I'd also like to see them able to move through closed borders, but they don't NEED to.