In essence, Real Madrid only needs to maintain its position with good results in every match and in this way, of course Real Madrid will remain at the top of the La Liga standings until the end of theseason. Apart from that, Barcelona and Girona are only fighting to finish in second place and not to catch Real Madrid and thus, on paper at least Real Madrid is certain to get the La Liga trophy this season. Unless, if for example Real Madrid gets a losing streak, then Real Madrid could be overtaken but yes, that is a scenario that I am sure will not happen. But regarding Real Madrid's next opponent in the Champions League quarter-finals, I think it was a final match that happened too quickly and of course Real Madrid and Manchester City both have to be able to make good preparations.
I don't think Madrid will lose balance in the remaining matches ahead, Ancelotti will try to stabilize the performance of his fleet so that it remains stable until the end of the season. If Barcelona draws against ATM, or suffers a defeat, then Los Blancos position at the top of the standings will become even more secure. Girona certainly cannot be ignored, but the threat and pressure they provide will not be the same as Barcelona.
Even though they had difficulty winning, Ancelotti fleet seems to be able to wipe out all the remaining matches in the future, the only tough match that might hinder Los Blancos progress is the El Clasico match. Apart from that, I think Madrid can run smoothly and maintain a safe distance at the top of the standings. With an almost complete squad, Madrid is getting closer to winning the La Liga trophy.
I'm in line with you regarding Madrid opponent in the Champions League, many hope it can happen in the final. But the match is still very long away, Ancelotti will focus completely on La Liga for the next month, we will see again how consistent the two teams are ahead of the semi final match, what is clear is that this match is difficult to predict.