Soraka + new Warmog

no, she doesn't really get to take advantage of it until way later and thats if she is building tanky items. not only that but if she buys a warmogs she is also spending 2.5k ish support gold on pure health just for the passive.

its a strong passive, but really a waste on raka imo as where she really shines is in team fights where she can keep someone alive forever as well as her whole team with ulti and then go back to healing. you will rarely have a team fight settle down for enough time for the passive to kick in and then she can go back in. she gets her healing done. gets relatively low on health. ults if she hasn't already and heals some more and then she's basically done outside of her Q's and E.

can't heal endlessly but she can heal quite a bit.

id imagine there would be situations where she'd be very strong with it though against say a heavy poke comp where she can heal up her teammates while they siege.

like pair her with Azir/Tristana against a poke comp? warmogs would be quite good. but it would be situational.

Also, you need 3k HP minimum for it to kick in

It's great for ARAM, but in a regular SR game there usually isn't enough poke before an engage to justify her spending so much into defensive stats. I think she needs 3 defensive items minimum to benefit from the passive, which would be soooo far into the game. (She might be able to make it with Warmog's, Ruby ss, and Spirit Visage.)

Only if she gets the gold to buy it alongside her other items needed for the passive

So basically if she gets enough for Warmogs quickly your probitly gonna lose the match even if she didn't get it

Well its just very strong if left unchecked if you burst her she can't heal while shes dead.

YES