Make Neutral Tiefling/Aasimar part of the Greater side again.

[magick in theory and practice]

Neutral tieflings and aasimar are par for the course. Putting that alignment behind an award also means an evil tiefling or good aasimar can't apply to change their alignment in a meaningful way in game as character development comes along. The sourcebook Races of Faerun talks about how a large fraction of both end up good or evil for obvious societal reasons - but that is not their core alignment due to free will.

But putting neutrality behind a major is in my opinion too stifling for character generation and character development in game (going from good to neutral or evil to neutral).

Genasi, who typically are meant to be along the neutral axis (the druid alignment hops) are neither restricted to those hops as a basic template and they are also not restricted to clerics with "their element" as a domain. Which is inconsistent to their own lore and I see paladins among that population all the time.

Neutral tieflings/aasimar were literally the "normal option" previously.

[The GrumpyCat]

I would rather this was kept. It's not my place to deny or approve, but my reasons are two fold.

1) - this means that the majority of Tieflings you meet WILL be evil, just like the majority of Aasimar will be Good. There will be exceptions, and they can of course be treated as such - but it encourages an amount of steryotyping that we kinda wanna see in the game to a degree, of distrust.
2) Neutral is the weak-sauce of alignments. I can make a Neutral Tiefling and run around helping out with charities, weeping over the death of butterflies, and preaching love, kindness and hope and probably still not really get a meaningful 'Stop that' By Dms. We just don't rp alignment in that much detail. Same with Aasimar. One can play a Lawful Neutral Hemomancer Aasimar who cackles as he slaughters NPCs and licks up their blood like an animal - and he can to a degree still make arguments that 'oh well yes, he's a bit naughty, he's neutral but he's not 'evil' -
Neutral covers a whole range of behaviours and is not really policed as much as 'good' or 'evil'
So it seems to me, if you want to break out of the typical archetypes of your races rp, (which I think you should tottaly be able to do! This change was brought in partly so one CAN play Good Tieflings or Evil Aasimar) you'll need to spend a higher tier award on it.
And if it's a concept you want to explore through roleplay? That's fine too. Spend the award, then contact the DMs asking for an alignment change, but for a note to be made on your sheet that it's possible to shift you back later,should your rp go that way.