Alternate summoning rule, to reduce clutter

[Melkiador]

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For Summon Monster 2-9 and Summan Nature's Ally 2-9, remove the ability to summon multiple monsters from lower level spell lists. Instead, you may summon a creature from a lower level list and apply the advanced simple template or the giant simple template to it.
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I have long had this idea for a rule to cut down on the clutter of summoning spells. I feel the basic idea is ok, but there are a few related issues that don't work with this. Most obviously the Superior Summoning feat's effect is based on summoning multiple creatures, but that feat is a prerequisite of other summoning options, and given for free by others. So, I feel I just need something good to replace that feat's benefit.

So, does anyone have any good options for what superior summoning could do? Superior summoning basically increases the power of summoning from a lower level list by 33% to 100%, depending on how well you roll. But I'm not sure how to represent that with bonuses, or even if I want to heap yet more bonuses on what's already a lot of possible bonuses getting added to these creatures.

[Dragonborn3]

You could always take notes from the Druid archetypes like Lion Shaman and get benefits for so morning specific kinds of creatures instead.