Monster Lord: -Yes.
Could it work for miniature creatures to get mini bonuses without the minuses for being mini?
How does the powerful build aspect of monster lord interact with trample, space, and reach?
Do you calculate reach distance from your medium space or can you still reach as far as if you were your Colossal size?
Can you stomp a city block while still appearing to be medium size?
-Only fill medium space, but can still trample and reach as original size.
-From your medium space.
Hang on, haven't looked in here for a while. That seems inconsistent both with how Powerful Build works, Prime's likely intention when writing Monster Lord, and all the time spent in Phantasy Star--for almost all of it Amaterasu was clearly a medium sized creature with colossal damage and grapple abilities, but without the accompanying reach. And it did come up on maybe one or two occasions where I went for the larger size to have the appropriate reach despite the to-hit/AC penalties.
Prime's exact wording was
"you get the Powerful Build trait, except you count as your original form's size rather than one size larger", and Powerful Build itself (quoting the Goliath Statblock) says "However, his space and reach remain those of a creature of his actual size."
The feat's already great as it is, without having the reach advantages--especially with reach as original size then having the question of whether you start counting from your own square or where your full size would be.