Acts of service is in a very obvious way Mickey's love language so that's probably why it feels like Ian barely did anything similar to that, because Mickey's grand gestures were obvious and loud but Ian had his grand gestures with him too.
Those grand but subtle gestures start in s1, he makes sure Mickey has enough money when he's in juvie, he even "threatens" Kash for it. In his own way, he protects Mickey. But it continues in s2 when Frank sees them and Ian tries to talk to him, he's desperately trying to protect Mickey again and make sure he doesn't go back to juvie. He tries, he tries to keep the secret that they were until that point for Mickey's safety even if he wants more, even he thinks they have nothing to be ashamed of. He does it anyway because that will keep Mickey safe and next to him too.
In s3, he tries to "rescue" Mickey from a forced marriage, from his dad. In his head, he's doing that. In his head, with his words and going there, he's helping Mickey. He, once again, desperately wants Mickey to see that he can get out there, that he can leave that behind and Ian would help him. He goes to that wedding thinking he can save Mickey from something he doesn't deserve, from something that is hurting him, that keeps him locked in a too dark closet. He wants to be Mickey's freedom but it doesn't work, Mickey's too scared and when you think about it maybe they were trying to protect each other. In s4, he's the only person that has Mickey's back when he comes out. He's there ready to fight Terry if that means there's going to be some type of justice for the hell Mickey had to go through because of him. He fights for Mickey and with Mickey, they share anger and hatred. And he's there to kiss Mickey's head when everything's over, he's there to hold him in the aftermath.
In s5, he breaks up with Mickey. And it might sound crazy but in Ian's mind that's an act of service, that's a grand gesture because he views himself as someone hurtful, destructive and he's pushing Mickey away so he doesn't get hurt, so he survives the destruction. He breaks up with him so he doesn't have to carry the responsibility that Ian feels he is, the chore that in his mind he is. He takes that weight off Mickey's shoulders and begs him to run away, he's not broken and that means that his destructive and hurtful nature can't be fixed, it's part of him and he doesn't want that for Mickey. He's protecting him, again. He's making sure Mickey is safe, again. Then, in s7 he's doing this too. He gives all his money to Mickey, he drives with him to the Mexican border and makes sure he crosses it safe and sound. It doesn't matter when he decided that he couldn't do it, the whole time he's making sure Mickey has a plan, and money and a real possibility of succeeding. And he doesn't wanna leave until he knows Mickey crossed that border, until he knows Mickey's safe again.
In s10, he tries to stay with Mickey in prison. He's willing to throw away his parole for him, to stay with him. The only reason why that doesn't happen it's because Mickey doesn't think he deserves those type of sacrifice and he doesn't let Ian do it, he doesn't belong there and Mickey won't let him be stuck in prison. Mickey thinks Ian deserves so much better than that, than risking that much for him so he doesn't let him sacrifice his freedom because he deserves it, because Ian was once the freedom he didn't have. But Ian wanted, Ian wanted to that so badly. In s10 too, Ian hears Byron talking about Mickey (we all know what he said) and he literally beats the shit out of him, it's like he's defending his honor.
Like I said Ian's acts of service seem more subtle because Mickey's are all these grand gesture. There's also the fact that Mickey doesn't feel worthy of those gesture, of those sacrifices so he doesn't let Ian risk anything. But they're there, Ian would do anything for Mickey too.
