1) A top 4 espada can destroy Las Noches in released state. So? What Ishida was speaking off, it was his Segunda Etapa release reiatsu, which dramatically changed the reiatsu nature itself of Ulquiorra, as you can read here. http://www.mangareader.net/94-802-10/bleach/chapter-348.html Ishida felt the reiatsu of some captains of Gotei and arrancars like released yammy mind you, he is keen at sensing reiatsu and Ishida is low captain level at least. But he was never as stunned as this, that reiatsu was superior to anything he felt, including Gin and Yammy released which is ranked 0 (highest ranked reiatsu of espadas). 2) While I agree AOE and power not always go hand to hand (the pressure of the attack matters) look here at LDR. http://www.mangareader.net/94-805-11/bleach/chapter-351.html The pressure of the attack is clearly enormous, as you can see he can tore tower of concret with its mere shockwave and the explosion not simply pulverized an area as big as Las Noches at least, but he also lifted sand at least to an height of twice-three times Las Noches. Las Noches is very big as pointed by Nel comment on the distance between the gates. He can fire it one after the another without effort. LDR can also be used as a mid range weapon. Ulquiorra defeating Aizen? Not really.. Ulquiorra is likely under absolute hypnosis, meaning he would not hit Aizen with LDR. And even without hypnosis, his aim is not that good (he missed a immobile target) so Aizen would not get hitted. If he get hitted by the explosion, then Aizen would at least be mid to badly injured by LDR (I doubt he can kill Aizen with LDR, as Yamamoto who is not much stronger than Aizen can survive badly injured a much stronger attack). He isn't crushing LDR barehanded like Scarmask Ichigo though, if he try that he would burn and possibly lose his hand. While with illusions, Aizen can easily avoid any damage to his person in the first place and surprise R2 Ulquiorra with a fully enchanted hado 90 enveloping him. 3) Vizard Ichigo stood no chance against R1 Ulquiorra, he released Segunda Etapa skyrocketing his power and it was used only to make Ichigo despair and make him give up on fighting. May I remind you that in HM arc after he beaten his "inner hollow" which nerfed him and gained the vizard mask, he regained "old man Zangetsu" as his main source of power? Which means that Ichigo was no longer nerfed. HM Vizard bankai ichigo >>> HM bankai ichigo>= SS bankai ichigo which could have cutted byakuya throat at the beggining of the bankai fight. R1 Ulquiorra could already crush an opponent much stronger than SS bankai ichigo even in R1. Ichigo winned against Ulquiorra SE only after he released his Scarmask godmode. 4) Kubo confirmed in the databook that espada are ranked on reiatsu levels. Aizen didn't know or saw his Segunda Etapa. Hard to feel his reiatsu presence if he didn't use anywhere near Aizen... So Aizen didn't feel his top reiatsu, the Segunda Etapa therefore couldn't be taken in account in the ranking and he couldn't rank him accordingly to it. Kubo portrayed him as having more reiatsu than Yammy released, hence he should likely be zero espada. And this comes from someone who is not a fan of Ulquiorra, mind you.