And entire secure wallet on a single chip. Create some custom spun chip with everything you need on the one chip.
Would eliminate a few attack vectors, but might add some more.
Was watching a youtube video about a company that built a custom piece of hardware for medical data pad for harsh environments, was essentially a custom android tablet with a HDMI connector but EVERYTHING was in 1 chip. RAM / ROM / Flash Memory, CPU, video processor, etc all in the one chip.
Probably won't help much, if at all. There isn't any proprietary secure elements being produced by any hardware wallet manufacturers. Designing one and manufacturing them would probably make the cost of one skyrocket, not to mention that smashing that many components into a single chip isn't common at all.
Communication between secure element and the MCU should be encrypted and if anything were to be extracted. AFAIK, some MCUs actually wipe their memory on bootup, even if the user doesn't do a clean shutdown. Would be better to just use a SE that allows for transactions to be signed within that, so keys are never sent out of it.