People shouldn't read too much into the seasons he plays with Ronaldo.
Someone said 11 goals and 11 assists? That's actually a fairly decent return for a team thats entirely in service to Ronaldo. He has dropped so deep and been their focal point in building up that he doesn't get to be a real striker.
If you want a comparison, think of Benzema, a brilliant false 9 striker (roams all across the final third), but had to play in service to Ronaldo at Madrid which hurt his numbers. Now being the main striker, he puts up great stats, which is no coincidence.
As shown above, when he plays as a true false 9 striker he is quite incredible. Now whether we need another player like him (or Felix) I don't know, but I don't see us ever being close to interested at 100m, the club just won't spend it.
70m and I think City would be interested.