I do find it difficult to design trees from 2D photos because depth and direction of branches is hard to determine accurately.
Given that, 2 options jump out at me immediately.
1: standard informal upright:
Retain branch A and work on back budding to build ramification. This could be a long low branch but I see a shorter more compact branch if possible.
Remove branch B - currently bar branch with A and growing from inside bend.
C becomes back branch - I hope that's where it points? but can still be flexible enough to wire toward the rear.
Reduce D and/or E to get back budding. Shorter, upper branches to right and rear?
F becomes the new apex. Wire more upright if needed. Reduce to stimulate buds and reduce length.
G: current apex is to the rear and thick. Remove.
Pros: Uses most of the current tree. Achievable in just a few years? Safe (most people's idea of bonsai) option
Cons: Safe option. Long lower branch may be reluctant to back bud.
2: cascade or semi cascade:
Check roots before deciding if rotating the trunk this much is possible. Some left side roots may need to be removed or jinned to allow this much tilt.
Lower branch becomes the new cascade trunkiline. remove or jin current main trunk and current opposite branch.
Cascade trunk will need to be built with growth from the remaining branch. Check that there is enough existing/possible sub branching to make this feasible in reasonable timeframe.
Cascade option is a little more radical. Involves removing almost all the tree you have purchased but may produce something different from standard informal upright.
pros: Something other than standard informal upright. Depending on left side roots, uses initial trunk bend to good potential.
cons: I can't assess that branch to see how ell it will make a cascade trunk. Quite radical reduction of current material.
These options are just 2 of probably many that your pine could become. Good luck with searching for the bonsai in this tree.