2 years after this car - I can't tell you how much I dislike how this car handles. Probably it's because the prior 3 cars were all BMWs.
I am not a professional driver nor do I track my car. I just drive to work and shuttle to soccer games on weekends if we happen not to take our other car (wife drives that) 2017 Audi Q7. That SUV has air suspension and ride and steers better than mine sedan.

a couple of issues I have, looking for your opinion
1. Lack of confidence when going fast when roads aren't straight. - feels like rear isn't "catching up" with the front like car will slide side ways. is that a steering issue? or springs are too soft so there is too muich body roll?
2. Lack of feedback from the road. In the bmw's you can feel every bump on the road through your steering wheel, or that's how I felt. I don't think I get any of that feedback, just a pretty loose steering wheel it seems.

So just the springs? saw a lot of H&R spring change out as I scour the forum. Or change shocks too? do coilovers?
Anyone from St. Louis and can recommend a good shop to do the work? since alignment will be needed after.

I have RW drive since hybrid doen't have 4 Matic. It has the same engine as a regular E350 V6 with an additional battery pack that adds a few more HP, and weight. But overall, think of it as a E350 RWD. It came with a sports pkg, but doesn't feel anywhere sporty.

Thanks!

Have you taken it to a shop to check for component wear? Ball joints, control arms shocks, tires etc will affect handling. Also the hybrid is pretty rare, maybe the weight of the battery pack really throws off the handling. What kind of tires did it come with? People also hate run flats, ride is horrible with those.

Nah.. that's how the car handled since day one. I thought I outgrew the "spirited driving" when i bought it. It even came with sports pkg. (though not AMG 18 wheels and tires). I had ask Koenig (sp?) to pull the built sheet, it has sports suspension.

The hybrid battery is tiny. in return, I get no spare. (I think standard car gets spare). Hybrid only gets 6 miles to the gallon better hahahahahaha. no wear and tear. only 21K so far since I owned it new.

I should say it drives and handles fine if you drive under normal condition, just following the traffic. It's only when I decide to drive it aggressively and not getting that feedback and confidence I used to have with the "other" brand...

Springs would be a good place to start. I installed Vaughan springs in my e350 and it made an appreciable difference in handeling. If you do go this route I recommend you also change the struts and shocks at the same time. Bilstein B-6 is a good choice for lowered cars. Assuming all other suspension parts are in good order your car should feel much tighter.

Have you checked your tires? Style, tread depth, etc..!