Well, some argue that the main differences in grip have to do with contact height.
The pro's all hit with pretty much the same forward lean of the racquet, regardless of what grip they use. There is also no direct correlation between swing path (how much low to high) and grip.
What does seem pretty consistent though is contact height. Eastern grip users seem to favor a waist to slightly above waist high contact point. SW starts above waist high to mid-chest level, and western users favor a shoulder high contact point.
This is one of the reasons most kids nowadays start off with a western grip (and is one of the reasons behind the push for quick start), when you're 4.5 ft tall, every ball is shoulder high or higher.
In practical terms, this means that switching to a eastern grip may not change anything. Most people I've seen that have changed grip, adapted their swing to the new grip and ended up pretty much back where they started. The exceptions were when the new grip was a much better match for the type of balls they were facing. I've seen several former college players (especially ones that started very young, or grew up on clay) with western grips, move more easterly and see improvements in their game because it more closely matched the contact height they were now facing.