Ajeel dries up Natsu in sandworld.
Brandish crushes him from the inside.
Bradman has untouchable
Dimaria timestop
August pure firepower
Irene enchantment
Invel freezes and kills him
Jacob transport
Neinhart summons Mard Geer
Walh was on par with Laxus strength.
Okay, so you're comparing Natsu to Spriggans in a battle sense to try and say he isn't Spriggan level power-wise? Well that isn't really doing much, most of those points are moot as they don't actually take much into account in a battle, plus when Natsu has defeated three Spriggans fairly easily it is very hard to deny he is "Spriggan level". But, I will address your points anyway:
- Natsu can literally evaporate sand with his heat as he did with Ajeel's ant-lion pit in Alvarez, so I doubt Sand World would trouble him too much, plus it isn't Sand World but Ajeel either using his Sands of Death (the tidal wave) or making contact with someone that will cause their body to lose moisture.
- Yes, Brandish could use her magic to expand Natsu's organs to the size where they burst and he'd die from that, I won't deny that. Whether she actually would is another story however, as she's said she wouldn't attack him, Lucy or Happy.
- Yes, Bloodman has intangibility and that works well against physical elements like Gajeel's iron. However, we've seen Rogue be able to hit Bloodman with his shadow magic, and like Rogue's shadow magic, Natsu's fire isn't purely physical, it's got another part to it apart from the the physicality of say a punch, so that should be able to effect Bradman if you catch my drift.
- Natsu(/E.N.D) moved through Dimaria's Age Seal, so that point is literally moot. He also took her out fairly easily from the look of it so I don't see what you're trying to prove here.
- So far we've seen Natsu be able to negate August's heat based magic which when you think about how he knows so much about magic and how strong he is, is a pretty decent feat. Yes, August would know a lot more magic and would probably beat Natsu in a one on one fight.
- Irene can enchant Natsu if she felt the need for it. But, if she was legitimately fighting him, so far we've seen her use a fireball against Acnologia which Natsu should be able to eat and get a boost in power from that. Again, August and Irene are the two Spriggans that would probably beat Natsu in a fight.
- Natsu can thaw Invel's ice as we've seen in the manga. I don't need to say any more on this.
- Yes, Jacob can transport Natsu away, but it isn't clear how that actually kills people. If he still has to do something afterwards with it, then I wouldn't be surprised if Natsu could still defend himself at the very least in Jacob's pocket dimension. Plus, if Natsu can land a hit on Jacob before he casts transport, it could well be over there.
- Neinhart summons Mard Geer who Natsu came very close to defeating when he used Dragon Force in Tartarus. Okay, Natsu has had almost a full year to get far stronger, how is Mard Geer going to keep up for long against that, especially if Natsu used FDKM or Dragon Force? It'd be over easily, plus Natsu has already shown he can defeat Neinhart with mere punches in base. Neinhart is no trouble here at all.
- Wall only did as well as he he did against Laxus due to him having an immunity to lighting and the fact that Laxus was affected by Magic Barrier Particles. Without the immunity, it could've been over a lot quicker, and seeing Natsu's attack power in FDKM is likely higher than Laxus', Wahl would be going down fairly easily.
Most of your points there don't hold much weight, and there's nothing to say most of those Spriggans would be up for long if Natsu attacked them when serious. When serious, he's taken out three Spriggans (Jacob, Neinhart (who was enchanted) and Dimaria) with ease, so there really is no denying that Natsu is on Spriggan level when it comes to attack power. He has some of the best attack power in terms of protagonists, and his speed and durability is also right up there. You can try and present situations where Spriggans could possibly beat Natsu, but that doesn't change the fact that he is on their level.