You can't change the past. And don't feel guilty - HS isn't the right choice for every family.
I think he will probably like it if he enjoys the other things you listed.
Just tell him you were wrong. Admitting that is a great lesson for him.
And if he hates it... Well, hopefully your newborn will be less needy then and you'll be in a different place and you may choose to try the HS route again.
SAHM to Magnolia May (09/10), Luke Russett (04/13) and expecting 11/16. Wife and best friend to my airman.