That's nice - lots of potential! What you need to do now is choose which branches to keep (hint - an uneven number is traditional), and decide if you want to chop some any, or all of them short and get ramification - more twiggy growth, more foliage, more potential branches. Right now it's a really nice ... shrub, but if you want it to be a 'bonsai' (though some say the point is that a bonsai should be a tree :-) and look older, etc., some work is definitely needed. Good trunk though.

OK.
So how big is necessary for a trunk to impart the look of an old tree? I intend to keep this tree (shrub) under 24" total.
It is currently 20" - so based on the total height versus dia. that I have studied - the ratio at 20" should be around 3" trunk.
The trunk is now 2 1/2". If I chop it back to just the vertical leader - remove all the branches..... then I am betting on the vertical leader to catch up and not have a drastic change from the current main trunk to the next section which is very mmuch smaller in dia.

This seems pretty iffy.

BTW - most of the pics I have seen of bonsai that have been proudly displayed in club competitions (and have won awards) have incredibly out of scale, thick trunks - If this is the acceptable "old tree image" that most are looking for, then they really need to spend some time in the wilderness looking at real trees. I am not looking to waste my time developing a bonsai that is an image of some mystical impossibitlity of real life. I am looking to sculpt a realistic image of a real life "old growth".