I am about to type something very similar to what
tvdtvdtvd said!
However, my next upgrade will be a FF sensor and it must not be something bigger and heavier than my current K3. It doesn’t matter Mirrorless or DSLR, If Pentax could offer a FF DSLR the size of K3, I will be very happy. If not, I will move on.
By the time I am ready to give up the K3, Mirrorless’s market would be more mature and hopefully the oversize lens design that try to correct all the problem known to mankind will be out of fashion. If Photography is Art; to me, Art is not about perfection, it's all about expression. Try to correct too many problems on the lens design just to come up with humongous lens size at the end is somewhat unnecessary and totally defeat the point of using smaller FF body.