Quote: Should I invest into Canon as well?
No matter if it's Canon, Pentax, or any other brand, I would not call an "investment" spending money on photography gear. At best, it's just an expense on which you can expect some return if you sell back the gear, assuming it still has a significant value when you sell it. But even then, it still a loss and not an "investment".
This reminds me a post I've seen on another forum where the guy answered to people why he bought a K-1 and not a 5D in face of the rumors on Pentax's death. He answered that, even assuming that his K-1 value would fall to zero, he would have loss, at worst, 2000$. Which is about the same loss, or even less, he would expect to have on a 5DIV or DS bought new and sold used a few years later. So, even in the worst case scenario, the K-1 was still a bet as safe as Canon to put his money on.