Tbh Im actually of the opinion that portrayal matters about as much as feats do, I think I oversimplified my comment just a bit so you guys somewhat misunderstood me, so I'll go into detail here. What I meant by the first part of my comment is that Mira scales to all spriggan tiers(except the top),
even Larcade, despite him being above the average spriggan(not much above).
I agree on Age Seal not being all that, and that higher tiers(probably even Larcade) could prob ignore it, but I disagree on the effectiveness of Larcades magic. His magic can be fought through, Eileen, Kagura and Sting all did it, I have no doubt Zeref, Laxus, GIldarts, etc could too if their lives were on the line. As for Larcade doing well against his direct counter, sure, but lets be honest, Sting isn't exactly top tier.
Now for what I meant about the second part of my comment, about spriggans not being all that different, what I meant was that they're overall strength is more or less the same to the point where the "tiers" don't mean much, not that there is no difference in their individual stats. I've said before, characters on the same general level can have vastly different stats. Some have better durability, some have larger scale magic, some have more potent magic, etc. The way I consider character stats in Fairy Tail is pretty much the same as how Mashima laid out the stats for the Demon Gates, except replace Curse Power with Magic Power.
Can't find a translated version but from top to bottom it's Health, Attack, Defense, Speed, Intelligence, and Curse Power. If I were to judge a spriggan like Neinhart it would be:
Health: 3000
Attack: 6000
Defense: 3000
Speed: 1000
Intelligence: 2000
Magic Power: 12000
And for a spriggan like God Serena it'd be:
Health: 4000
Attack: 5000
Defense: 12000
Speed: 5000
Intelligence: 5
Magic Power: 10000
That's generally how I've thought of FT power levels since the end of Tartaros. And to a lesser degree even before GMG. As for Wahl vs Ajeel. Spell size means nothing to me, so Wahl busting a bunch of buildings doesn't impress me. Ajeel moisture drain is mediocre too. Killing Wahl with a named attack rather than a nameless nuke does get some credit from me, but not enough for me to consider them a tier apart. The stats I'd estimate for them are:
Wahl
Health: 5000
Attack: 5000
Defense: 7000
Speed: 5000
Intelligence: 3000
Magic Power: 9000
Ajeel
Health: 5000
Attack: 3000
Defense: 4000
Speed: 5000
Intelligence: 2000
Magic Power: 10000