I usually play in creative mode, but thought it would good to try and build something in survival mode. Few observations/suggestions:
In creative mode you can resize things down to 0.01 but i notice in survival i am only able to get as small as 0.1. I am not sure why this restriction is there. I dont see a problem with letting me chop down a tree and whittle it down to a toothpick in size .
In creative you can enlarge beams up to 15.99 in size. I understand you would not want this in survival, but it can limit what you can build while in this mode. My suggestion is if someone wants to resize a beam say from 1 1 1 to 1 1 2, then they should be allowed to do this, but it would then remove 2 beams from their inventory. If they only have 1 beam in their inventory then they could get an error message. It would be a simple math problem to figure out how many beams needed to be removed from the inventory to get the size the player is trying to create. I suggest this for a few reasons, One- because you are limited to max size of 1 1 1 you end up using alot more beams which then increases lag. Second, not being able to increase the size of a triangle can limit some builds, or at least make them a lot harder to build. And finally, if you are using the snap feature to place your beams, you loose a pixel (or whatever) in length, so if you have several beams that have been snapped together and you want to match the same height/length you have in blocks you will find your beams to be a bit shorter than your blocks. This is a problem because you have limited the size on the small end and large end. For example if i have a 4 blocks on top of each other and then i want to place 4 beams the size of 1 1 1 next to the blocks and use the snap mode i will find that my beam column is like 0.04 shorter than the block column, in survival i cant make a beam 0.04 high to fill in the size difference and i cant expand one of the other beams to 1 1 1.04 to make up the difference.
I hope this is not too confusing, but basically i would suggest to allow survival to reduce beams down to same size as in creative. and to allow beams to be enlarged past the 1 1 1 but to just use up more beams from the inventory.