I purchased both clear and core spark themes from themeforest. Originally, I used them as a guide while learning laravel. I would not do the same, again. Looks very clunky....
I always have had issues with the supposed license with ThemeForest, the way I read it is if you charge for access (sell) to your SaaS then they want the Extended License.....
However Re-templating Spark has always been a headache for me. The Bootstrap that comes with Spark has enough tweaks from the generic that I've spent a while chasing my tail tweaking css etc.
Regards the License from Themeforest, I did check back with them on exactly that point, and they told me the Regular License is sufficient for that saas case.
@EventFellows -- any success on this? I'm in the same boat right now; looking for a more comprehensive theme for my admin dashboard I'm building and don't want to build from scratch on-top of the Spark structure.
My biggest concern is finding something that plays nicely with Spark's Vue components. Definitely don't want to have to re-write everything. Thinking a simple HTML5/Bootstrap theme will be the answer.