I also think the 150's will be too stiff unless you leave them very long or add even more point weight. You might call one of the sponsoer's that carry the Heritage 90's, I'm thinking the brand new stock is a little longer this year but we don't carry them so I'm not sure on that.
We have the CE Predator II's in 30/50 (.500 spine) that should work well for you, you can get a 30.25" max length arrow from those if you leave them full length. Like the Heritage 90's, they are slightly smaller diameter so we carry the extra nocks and inserts as well.