I'm on the lighter side <180lb so any mattress with springs has always been uncomfortable because I don't have enough weight to compress them

I've been happy using a solid foam mattress. Although I don't know if its memory foam 

 I slept on a pocket sprung mattress when I went on a cruise last year and I've never slept better 💪 

 I have a spring mattress with a foam topper. 

But I'm seriously considering getting rid of all of that and just sleeping on a few blankets directly on my plywood platform.  

 You're the third person to tell me this, I have to figure out if I could sleep on such a hard surface  

 It takes a while to adjust. I go camping and have an inflatable, and I insulated air mattress. That's more comfy than most things to me. 

I'm getting less comfy on mattresses at I loose weight.