When I built my house, I always wanted a very large space in the living room for just the thing you are doing..........putting in one HUGE Christmas tree. Considering it took forever to do in the interior finish of this beast, and considering I became almost brothers with the trim carpenter, and considering it took over TWO Christmas Seasons to finish the interiors, my trim carpenter was around to watch as we attempted to hoist up this monster Christmas tree. I had the same problem........looking like a fool trying to install the tree base into a homemade tree stand that actually would fit the base ok, but unless you are very fortunate and have a "perfect" tree, nature plays cruel tricks and the tree is not the balanced beauty that it was in the field.
Anyway, after letting me struggle for quite a while, Gary (the finish carpenter) goes out to his truck ( a new one that "I" probably paid for, by the way )takes out his skill saw and makes me an "X" out of 4' lengths of 2x4's and places an old plastic mastic bucket onto the "X", puts this monster tree into the bucket, and then takes some bracing (and it needed the bracing) made out of some 1-1/2" metal studs we had laying around and screws the bracing to the base and then into the tree as required to hold it up. Very sturdy. Very safe. However, next year I bought a different species of tree and had a little more trouble getting the bracing to get by all the limbs within the tree. The following year, I solved this problem. I buy only 8'-9' TREES and I can utilize a STA?NDARD store bought base.