Whats the point of the barrier spell? It sounded good to me at first.. and then I thought, why would I not just heal? It is around the same base hp is it not? And the heal doesnt run out of time.

Im sure im missing something, lol. Just curious!

but what if they ignite you?

There are lots of effects like the summoner spell Ignite or Tristana's Explosive Shot that can reduce heal, shields, on the other side, cannot be reduced.
Not only that but also, shields can go over your maximum health, heals can't.

That makes sense, thank you

Wait i thought it was just replacing the B button not actually becoming a summoner for it?

Also, barrier blocks more.

And effects over 4 seconds, so if you take burst a couple seconds later it will block it.

And on the new ARAM map you get 20% healing reduction.

Personally I don't see a reason to use heal :|

In general, shields are more timing and skill-reliant than heals, and provide much more gameplay. We also wanted a Summoner Spell tailor-made for melee champions, who have issues on the map since they tend to go all-in.