While I agree, Vader definitely had the advantage when he attacked the Jedi Temple. The whole idea that they were only brought down by a elaborate plan is hardly a testament to their strength. Their downfall had nothing to do with a full on battle, face-to-face like the Great Galactic War or the Jedi Civil War, they were stabbed in the back, no means of strength could have prevented their destruction.
The Jedi Order of the Old republic shouldn't be dismissed as weaker, if anything they were stronger, battle-hardened. The Jedi of the Prequel era had enjoyed a 'Golden Age' - 1000 years of peace. Yes they had time to improve their training and grow their numbers but they had no real enemies - sith - to test themselves against. The fact that Ventress defeated Jedi so easily, such as Luminara Unduli (I watched the fight recently, if Ahsoka hadn't intervened, Ventress would have killed her) is a testament to this.
Bastila Shan participated in the Jedi Civil War, so we can assume she had experience with sith - more than the Jedi of the Prequel Era. This already gives her an overwhelming advantage. Consider that during the clone wars there where, what, 3 sith operating at any one time. So we can surely say that many of the Jedi, including masters, had never fought a lightsaber wielder who actually wanted to kill them, and was sith.This could account for Ventress' prowess in battle against them. Bastila had experience, she would not be so easily killed.
You are absolutely right man! Not to mention that these "forms" are for to use the force easyer against your oponent, because the REAL masters (as Yoda) not use light saber forms, because the force guide his light saber. This was described well enough in the Darth Bane: Path of Destruction. That's why this Dark Jedi could defeat Lumia or Plo Koon... not like Obi-Wan ... and a little hard to see something like " Ventres" AND everyone in the prequel era could beat anyone... for example Exar Kun almost killed Luke and he is even older then Bastila, and Luke not in the Prequel Era. Pure Aurbere forget it every time that the Jedi Civil War or the Returned Sith Empire times the anchient times... and in these times were lost a lot of knowledge about the force, and yeah I know it because the Jedi, BUT the Jedi never used these knowledge!