I am an active powered airplane pilot, an active glider pilot and an active powered airplane instructor so I think I can offer some informed comments
First several post already seem infused with the "Glider pilots are inherently superior to powered airplane pilots" hubris that is unfortunately both disappointing and IMO largely unwarranted.
One big myth is that glider pilots are going to be instant masters of the PFL. My experience has not demonstrated that at all. Glider pilots are not inititially well prepared to deal with the challenges of glide path control in the PFL case because they are used to having such huge control over their glidepath. You can get well away from the optimum flight path in a glider and still fix it in ways that are impossible in a gliding powered airplane. Also the speeds the powered airplane will fly can be up to twice as fast as a glider approach speed so things happen a lot faster.
Glider pilots learn to adapt of course, but proficency will often take about the same amount of practice as someone who has never flown a glider.
However that been said I do think there are good reasons to start with a glider license.
First learning on the glider will concentrate on the pure stick and rudder foundation skills without the distraction of a panel full of instruments and managing the engine. Mastering those foundation skills will serve you well in what ever you end up flying.
Second glider instructors are held near the top of the glider community in terms of status. Powered flying however is the exact opposite. They are often low timers putting in time until a "real" job is available. So the chance of getting a very good introduction to general foundation flying skills is greater in gliding.