So after some time we are finally getting some answers to questions that many have only speculated up until this point. We have learned somethings that can finally put to rest some of the notions that many of us have been fighting about for some time. While not so many questions are answered in certain cases, there are answers forthcoming for the Hollow, Arrancar, Espada and Vasto Lorde questions that plague the Bleach Fan base.
1.) Most of the Espada are Vasto Lorde. Who the most refers to is questionable my general thought is it must extend from the 0- 4, and 5 maybe 6th Espada.
2.) Tia Harribel was most certainly an Vasto Lorde-class Menos Hollow who eventually became an Arrancar/Espada under Aizen.
3.) Stands to reason as his form and power in Hueco Mundo would suggest Baraggan is also originally a Vasto Lorde-class Menos Hollow prior to becoming an Arrancar/Espada under Aizen.
4.) The only issue is Starrk he very well is likely a Vasto Lorde-class Menos Hollow as well but there is also open belief to the point that he maybe a naturally occurring Arrancar. Seeing his soul separation ability didn't require gaining power from Aizen's use of the Hogyoku. Leaving cero which any Hollow or arrancar can perform. This one is still confusing. Though its a safe bet he was Hollow and not an Arrancar.
5.) Starrks possible point of being Primera Espada is due to his power being so great other Hollow couldn't be near him without dying even Baraggan didn't have that issue so Starrk may in fact be more powerful then Baraggan despite the latter's lofty status in title prior to Arrancarfication, he just didn't flaunt his power as Baraggan.
6.) Most the Arrancar in Aizen's service apparently were given their powers and made into Arrancar by Aizen's use of the Hogyoku. As we are seeing Arrancar that were formerly Hollows with powers they didn't originally possess and Vasto lorde -class menos all retrain humanoid shape reminiscent of their original hollow form partially or completely.
7.) Vasto Lorde are in fact not as powerful as an Arrancar.
8.) Apparently Hitsugaya's explanation of Vasto Lorde was not entirely correct. If what we now know is true Vasto lorde have been under are noses for quite some time and it amounted to a whole lot of the typical hype surrounding some of the antagonists we see in various stories across the board. We hear how dangerous and illusive they are and make wild assumptions as every person on this site who supported Aizen or the Arrancar has done. Now we find out the Vasto lorde-class menos Hollow we were so afraid would become Arrancar gaining even greater power to destroy really weren't that big of a deal. Starrk beaten by a Shikai, Baraggan outwitted with his own insurmountable power used against him, i freely admit he was the hardest to get past in this regard, mostly what we feared of vasto lorde made arrancar. Harribel well we know what happened there and Ulquiorra for all his forms and power was beaten by the inconsistent Ichigo or rather his inner hollow possessed hollow form.
Hopefully we will know more soon, but this case seems to be pretty much closed. Unless there is something else I forgot to mention.