Building a custom Eldritch Knight/Arcane Trickster spell list

[Sindeloke]

So suppose we were to put more thought into these two subclasses than just "oh, throw some wizard spells at them and call it a day." What would be an appropriate, thematic, synergistic list of spells for each of them to have?

We can go even further: what if we posit that the Bard's spell-stealing ability has the clause "you can only select a spell that is either natively a bard spell, or on at least two class lists (not including special spells granted to subclasses)." We can now go nuts with the Paladin/Ranger "class features masquerading as spells" thing; either subclass could have a 4th level spell that's properly calibrated to the power level of an 18th level character, because that's the lowest level it will be available to anyone. What spells would you invent under that condition to give these classes some oomph?

I have few ideas at the moment, except that Haste and some form of teleportation seem mandatory for the EK, silence and darkness are mandatory for the AT, and both of them benefit a lot from bonus action spells since their action is already typically spoken for (at least in combat) by an attack that their magic will never approach.

[tieren]

Not really sure what you are looking for here.

You know both EK and AT get a few of whatever spell they want right? I mean if your EK doesn't already have haste and misty step by level 14 you are doing it wrong.

If you want a lot of spells from a different school you should probably be thinking more about multiclassing.

[Daishain]

Not really sure what you are looking for here.

You know both EK and AT get a few of whatever spell they want right? I mean if your EK doesn't already have haste and misty step by level 14 you are doing it wrong.

If you want a lot of spells from a different school you should probably be thinking more about multiclassing.
I haven't built an AT yet, but when messing with EK, the list of spells I actually wanted from the evocation/abjuration list was smaller than the number of spells he could pick from said lists. (Shield being among the major exceptions) At no point in a character's development should you be exclusively picking between things that are completely useless and things that are only mostly useless.

If a spellcaster is going to specialize in only two schools, those schools ought to have more than a tiny handful of spells that actually do them some good. Simply being able to swap Evocation out to something else would do worlds of good in this regard.

[Grimstaff]

So suppose we were to put more thought into these two subclasses than just "oh, throw some wizard spells at them and call it a day." What would be an appropriate, thematic, synergistic list of spells for each of them to have?

We can go even further: what if we posit that the Bard's spell-stealing ability has the clause "you can only select a spell that is either natively a bard spell, or on at least two class lists (not including special spells granted to subclasses)." We can now go nuts with the Paladin/Ranger "class features masquerading as spells" thing; either subclass could have a 4th level spell that's properly calibrated to the power level of an 18th level character, because that's the lowest level it will be available to anyone. What spells would you invent under that condition to give these classes some oomph?

I have few ideas at the moment, except that Haste and some form of teleportation seem mandatory for the EK, silence and darkness are mandatory for the AT, and both of them benefit a lot from bonus action spells since their action is already typically spoken for (at least in combat) by an attack that their magic will never approach.

April's Unearthed Arcana column has a good article on creating custom subclasses. That said, its easy enough in the case of the EK/AT to just let the player pick two schools of their choice, instead of adhering to the 2 preset choices. At no point should either have the breadth of choice or versatility of a full-class spellcaster, though, as that would be essentially coming up with gestalt classes.

[DivisibleByZero]

I haven't built an AT yet, but when messing with EK, the list of spells I actually wanted from the evocation/abjuration list was smaller than the number of spells he could pick from said lists. (Shield being among the major exceptions) At no point in a character's development should you be exclusively picking between things that are completely useless and things that are only mostly useless.

If a spellcaster is going to specialize in only two schools, those schools ought to have more than a tiny handful of spells that actually do them some good. Simply being able to swap Evocation out to something else would do worlds of good in this regard.

It's less of as problem for ATs than it is for EKs.
But even with that in mind, our table allows ATs and EKs to choose a third school to access. So every EK or AT has the two schools normally granted (as common abilities of the subclass), plus a third of their choice (to customize and differentiate individual characters within the subclass), as well as a few that can deviate from those three schools (one from each spell level, as normal).