Again your sentiments resemble my own. There doesn't need to be excuses for Ole to say that he's done enough to be backed further but also that ultimately its disappointing to lose a final we should have won.
I don't think we need to spend anywhere near 300mil. I think we could get the 3 players we need for around 100-120mil. That's beside the point, everyone in the world can see our weaknesses and until he has the opportunity to address those, like Klopp had with Lpool, like Pep(a few times) had with City I'd hold off from saying he has to go. The next manager is going to come in and at the very least need to address those same areas before he's expected to win things.
Your opinions on the final are similar to mine too, I don't see it as black and white if you don't win you're useless. Even if we played horribly and lost I still wouldn't think that because throughout our European campaign we beat PSG, Leipzig, AC Milan & Socieded. We've proven we can beat big teams. We've proven we can get past a semi-final. We should have won that final but the whole tenure cannot be simply summed up with losing a final on penalties, when everyone but our keeper scored.
We should rightly criticise last nights performance but it quickly goes beyond judging moments or games on here.