Drow SR - Would 57+ be enough to have some use EE content?

[LotM]

Drow SR currently caps at 42.

+ 6 from paladin enhancements

+9 with twisted in Serenity

Thats 57 potential SR. SI there another stackable buff?

Is that figure relevant against the caster levels of EE content?

Thanks.

[Grailhawk]

Not 100% on this but fairly sure mob Spell Pen = Mob CR, So it may help in some lower level EE's but will not stand up against higher end quests with mob CR's in the 80's.