Musing on Spell-Like Abilities in Echelon

In almost all editions of D&D many creatures have abilities defined in terms of spells, such as the succubus’ suggestion. These are like spells (subject to spell resistance, etc.) but not exactly (each may be limited to a certain number of uses per day, and they don’t share all the casting requirements of normal spells). ‘Spell-like abilities’ is an appropriate expression.

I have never much cared for the ‘uses/day’ style of limitation, and I’d like to see it gone. All creatures in Echelon have magic points. These are used by casters to fuel their magic, other characters might use them to power magic items, and so on.

Using these points to pay for the use of spell-like abilities makes sense. However, at that point they become even more like spells.

By itself it doesn’t bother me, but it does lead me to question whether the distinction between ‘creature with spell-like ability’ and ‘creature that is a spell caster’ is relevant any more.. and if not, should a creature with spell-like abilities, inherently magical, have that count toward ‘normal’ spell casting?

I see several ways forward with this:

• Treat as spells. Casting them requires magic points, just like spells, and they interact with all other rules as spells do. This suggests that the talents that grant access to these abilities will behave either as casting tradition cornerstone talents or as spell knowledge common talents that provide a training bonus.
• Treat as magical abilities. Using these abilities requires magic points, just like spells, and when used they interact with most other rules as spells do (subject to SR, but don’t require material components). Both cornerstone talents and common talents can grant access to tier-appropriate spell-like abilities. These will be narrower in scope than casting tradition cornerstones or spell knowledge common talents and don’t provide a training bonus, but they can provide direct access to higher-tier spells than either of the other two talent types.
• Treat much as D&D 3.x. Using these abilities consumes ‘uses per day’, and when used they interact with most other rules as spells do (subject to SR, but don’t require material components). No interaction whatsoever with the casting system.

What are some other possible approaches?