Hi Arial36,
Welcome to the Mattress Forum! 
Thank you!
The Tuft and Needle doesn’t contain any memory foam, so it would tend to be more “breathable” and less “heat retentive” than an item using memory foam in the upper layers. I’m not sure if you’re looking for an all polyfoam mattress like the Tuft and Needle, or if you’re considering other options like innerspring or latex.
I’m not sure how long you’ve had your Tuft and Needle (or if you still have it), but all mattresses will go through an initial “break-in” period where they become a bit more plush, usually most evident in the first six months or so.
I’m not sure what you’ve read since you found the site (you said you’ve been doing some reading but I’m not sure if that applies to this site or others) but just in case you haven’t read it yet … the first place to start your research is the mattress shopping tutorial here which includes all the basic information, steps, and guidelines that can help you make the best possible choice … and perhaps more importantly know how and why to avoid the worst ones.
While I can certainly help with “how” to choose … It’s not possible to make specific suggestions or recommendations for either a mattress, manufacturers/retailers, or combinations of materials or components because the first “rule” of mattress shopping is to always remember that you are the only one that can feel what you feel on a mattress and there are too many unknowns, variables, and personal preferences involved that are unique to each person to use a formula or for anyone to be able to predict or make a specific suggestion or recommendation about which mattress or combination of materials and components or which type of mattress would be the best “match” for you in terms of “comfort”, firmness, or PPP or how a mattress will “feel” to you or compare to another mattress based on specs (either yours or a mattress), sleeping positions, health conditions, or “theory at a distance” that can possibly be more reliable than your own careful testing (hopefully using the testing guidelines in step 4 of the tutorial) or your own personal sleeping experience (see mattress firmness/comfort levels in post #2 here).
As you stated that you’re looking to stay local, and you’re in mid-Michigan.so subject to first confirming that any retailer or manufacturer on the list you wish to deal with is completely transparent (see this article) and to making sure that any mattress you are considering meets your specific criteria and the quality/value guidelines here … the better options or possibilities I’m aware of in and around the Lansing, MI area are listed in post #2 here. The list for the Grand Rapids/Holland area is in post #273 here. There are also lists for the Detroit/Ann Arbor areas in post #2 here and for the Portage/Kalamazoo area in post #2 here and
If you are near Lansing, you may wish to consider:
www.capitolbedding.com Lansing, MI. Regional wholesale manufacturer that has been making mattresses for over 65 years and make a wide range of good quality/value mattresses that would be well worth considering. They are also transparent about the materials they use inside their mattresses. They are sold through retailers in the area and have a store finder on their site (the ones that are closest to Lansing are included in this list). They make a wide variety of mattresses, including polyfoam, and if you’re looking for something specific they might be quite helpful for you.
I’ll be interested in learning about your progress.
Phoenix