I'm not REAL experienced compared to some others, but probably more so than not, so I'll say a bit.
It's always hard for me to render an opinion about a tree seen only in photos, of course, even under the best of circumstances, and especially with a wild tree. Typically, I kind of live with a tree for quite some time, sometimes years, sort of formally and informally studying it over and over again before I make a committed styling decision. This is especially true on a fine old piece of material like this one.
Unlike, say, Ponderosa pines, the trunk and thick branches on old junipers are seldom flexible enough for me to consider bending - even with benders, rafia and rebar, hollowing out the heartwood, etc. Others here may be more bold, however.
These trees are often impressive enough to me just as they are, such that I find it easy to work with what they present without such maneuvers. Removing branches and foliage that doesn't fit, developing new foliage in areas where it is thin, bending branches that can be reasonably bent - that's about all I attempt, except to accentuate the deadwood which often features so prominently.
It's probably no mystery that I'm a big fan of Dan Robinson's "Focal Point Bonsai Design", in which a deadwood feature, espcially a prominent one found down near the base - either natural of created - is so often chosen as the "focal point" on a tree like this one. The styling of the rest of the tree is then chosen to frame and accentuate that focal point, such that decisions about trimming and branch/foliage placement become more logical.
This tree has a very interesting feature of exactly this sort down at the basal crotch. It is visually striking, and tells something of the tree's age and history. It is the most obvious feature that could make this tree fascinating. It would, most likely, be my focal point. I'd look at it and study it over and over again, and over time make some decisions about how the remainder of the tree could be manipulated to draw the eye to that feature, how the branches and foliage could be designed to frame, point to, or accentuate that feature.
That's how I'd approach it.
It's a nice piece of material. Good luck!