Are Shirou's ideals viable or unrealistic and broken?
It's made pretty clear his ideals, when taken to the extreme, are unrealistic. In moderation, it's not such a bad thing to want to try and save the people in front of you, but if you go too far, it overtakes your life and forces you to make some bad decisions.
His ideals and his single minded determination towards achieving whatever goal he set himself got him laid so it can't be all bad. https://www.youtube.com/watch?v=crUF7Di3Dhc
>>284805274idealcucks BTFO
Shirou is clearly a special individual with abilities beyond that of a normal human. It's far from ridiculous for him to want to use those skills to help others.