Search here for a thread, actually multiple treads using my name or Dream saddle.You’ll find a lot of suggestions. I’m still nervous on my new saddle a Phillipe Fontaine trekking that i got so cheap at the stuben sale, deep seat high cantle, cut back gullet.I bought 2 and have one on e-bay now.
Like you I have weak leg strength , I was riding a STeele planation saddle which felt safer but didn’t fit my horse and would not work for eventing.
You can jump some in the trekking saddle and there are several french saddle makers who make good trekking saddle(brain fog) which work for pleasure riding and lower jumps.
If you find something that helps you feel more secure do post it as I’m always looking. My horse is wide but has some withers.