hello, you are exactly right, the stand is like seven inches higher, the center of balance is now three to four inches higher and the stand is less stable.
The intent of the the wider wood at the bottom is to spread the load of a wider area, (not really a concern here as the floor is a good solid concrete), but with a wider bottom piece the stand is less likley to rock or roll from side to side, i,e, earthquake stuff..
With the way you have it now, the stand will either try to tip to teh side and break the wood apart from the bolt or bend the bolt or the metal stand it is bolted to (kind of like a locked joint, think kneecap) it doesnt take much to push that joint in on a lateral direction, significantly less force then you would think.
The wood length under the edge of the stand will be another potential issue as the wood compresses right there and starts to split, and will split right to the bolt.
Anyways, the likelihood of any problems is few and far b
between, but if you got the chance you make the problem truly insignificant.
If it were me, I would change it out.
And actually, I would think about using those concrete piers they sell at home depot and placing a wood frame ontop of that then the stand.
But hey, it is just my opinion, and like I said, the chances of failure are pretty low as you have it now...
good luck, keep up the pics and the progress reports, so I can armchair some more...
bill