Suspension swap ZHP tp M3

I have 2002 M3 vert which I love driving but being 66 I am starting to find the suspension a bit harsh. Same goes for my wife. It is a DD on nice days and I never track it and honestly don't drive it that hard, but I do like the power delivery when I step on the gas. I would like to modify my suspension towards the comfort end of the spectrum. Do you think that swapping out the springs, dampers and sway bars from say a 300CI ZHP vert would move me away from the harshness of the normal M3 ride? My wife has 2003 325i sedan and after driving the M3 I do find it a bit bouncy so I do not want to go to that end of spectrum. I have never driven a 330 ZHP so I don't have much to compare to. I would really like to keep the M3 and sort out the suspension but if I can't I would also consider to sell the M3 and buy an E93 335.435i ( or maybe 330CI ZHP). I am thinking a 330CI ZHP would be my preferred destination if do go this route but would prefer to keep my M3. I do have 2006 E91 wagon so I know the feeling somewhat of the suspension of that generation but I really like the communicative nature of the e46 chassis.
It would be great if someone could comment on this approach or suggest another that will get me to a somewhat softer suspension setup for my M3 vert. I see a lot of posts for swaps from the M3 to the ZHP and I know that this kinda backwards. I guess if it works one way it should work the other way. I can swap out suspension parts myself but I would like to know before jumping into an exercise like this that it will get me to where I want to be. I don't have the time or resources to be swapping parts in and out of my suspension until I get it right. It seems like transferring the suspension from a 330CI ZHP would work but I am concerned that there may some nuances that I am missing. I understand that pretty much springs, dampers and front sway bars are interchangeable between the regular e46 ZHP and the e46 M3 as long as the bushings and strut bearings are changed as well. Can I keep the controls arms and king pins? It seems that the rear sway bar is an issue. Maybe I would need a different rear sway bar. If someone is a suspension guru or knows of one it would awesome.
You guys are much more well versed in these issues than I am so please chime in and help me sort this out!
TIA from a ZHP mafia newbie

I have both the ZHP and M3. Sell your M3 and get a car more suited to how you want to drive.

Welcome - Depending on where you’re located, I’m sure someone might be willing to let you test drive their ZHP.

Thank you. I am considering that option. The S54 engine is such a sweet power plant, it is difficult to give it up.
Located in Odenton MD 21113

I don't think you need a total replacement to tame your M3. I think you'd be fine just replacing the stock struts/shocks with some Koni STR.T's. If you need new tires sometime, you might consider moving to 17 inch wheels.

Thank you for your suggestion. It seems like you may have some relevant experience. I looked into going down to 17” wheels and a four sq setup but I had too many bad experiences with scammers and had an urgent need to replace my rear tires so I let it go. I just purchased a complete used ZHP suspension with everything needed to install, so I will stick it on there and see how it feels. I get it that I may have to mess around a bit to find out what works for me (and my wife). If I think that the ZHP setup is close to what I want then I will look into what permanent struts and shocks to put on there. Your suggestion may come in handy. I am wondering if I will run into problems with alignment and if I should stick camber/castor plates in there when I install the ZHP setup. For now I will run with the m3 sway bars.