Hi lalunia,
While a mattress topper combination can have many advantages … I wouldn’t suggest trying to build a “sleeping system” this way unless you can test the same combination you plan to sleep on in the store. It’s much more difficult to build a sleeping system with two variables because when you buy a mattress separately from the topper without testing the combination it can be difficult to know how the specific combination will work together and interact with your specific body type and sleeping positions. There are many cases where this can be a good option if there are no better choices (such as a mattress exchange where there are no good quality/value options available) but in general it’s much more effective to get as close as you can to matching your needs and preferences or what I call PPP (Pressure relief, Posture and alignment, and Personal preferences) in the store and then doing any fine tuning you may need to do (and hopefully very little) after you have slept on the mattress for a while.
If you do decide to go in this direction … it would be much better to do it with a very firm mattress with only very thin and firmer comfort layers that use high quality materials rather than adding a softer topper to a mattress that already has thicker softer comfort layers (such as either a plush mattress or pillowtop both of which could have very similar layering in the comfort layers) and taking the risk of alignment and back issues from lack of support. It would be important to make sure that the base mattress was suitable for a topper as well (didn’t have thicker layers of lower quality soft polyfoam in the comfort layers). It’s always much safer to work with only one variable (either as a mattress or as a combination) which you can test in person.
Of course if the retailer or manufacturer that you are dealing with has the combinations that you want to test then a mattress/topper combination where you know all the layers and there are no weak links has the advantage of being able to either change or replace the topper without having to replace the entire mattress should it wear out faster than the mattress or if your needs and preferences change over time.
Almost any company can make a “natural, supportive, but cushy luxurious feeling” mattress but different people may have very different ideas of what this may be or feel like depending on their body types, sleeping style, and personal preferences and perceptions. Your own personal testing will tell you which mattress is like this for you.
VI-Spring makes very high quality mattresses with very high quality coils and natural fibers but it’s questionable whether it would provide the two basic functions of a mattress any better or be more durable than another mattress that used very high quality materials that was a fraction of the cost. Of course a mattress like this (innersprings and natural fibers) would be very breathable and very temperature regulating but so can many other mattress types. With ultra premium brands like this you are buying a work of art as much as you are a mattress. Post #2 here has more of my thoughts about this.
Like all airbeds … the comfort layers that go over the air bladder are the biggest part of how the mattress will “feel” for most people and these would be the same material choices that could be used over any other type of support system. An air bladder is a support component not a comfort component (although like all support components it will have an effect on pressure relief to different degrees depending on the layering of the mattress) and when you compare it to other types of support systems it doesn’t fare very well. You can see more of my thoughts about air bladders as a support system in this article but in general and for most people they would not be the best choice IMO.
The best advice is always to “find the experts” so you don’t have to become one, test and become familiar with different types of materials and components so you know which combinations you prefer and don’t have to go by “theory”, and always make sure you test mattresses as objectively as possible so your body can tell you which one provides the “best” PPP and then your mind can look at the details of every layer to make sure it has no weak links and has the quality, durability, and value that will keep it feeling the way it originally feels for much longer and is “worth” the money you are paying for it.
Phoenix