I have to admit that reading the spoilers so far I'm a tad concerned that Ianto is, for the most part, going to be defined by his relationship with Jack. Phrases like 'he becomes Jack's loyal soldier' and consistent mentions of him only in regard to what's going on between them don't sound promising.
I really hope they give him something else significant to do other than be Jack's love interest because he's got way more potential than to be only that. Sometimes however it does worryingly seem like the writers/producers have gotten so caught up in their ship that they do little else with the character. Which is daft because he when you consider the great TV ships - Buffy and Angel for example - the ship is obviously important but not the only thing about those characters. They didn't revolve around it. Buffy had an awful lot more to her. When Joss realised that Angel was becoming solely defined by his relationship with Buffy and that they'd written themselves into a bit of a corner there, he gave the character his own show rather than waste him. The character was more important than the ship but that doesn't always seem to be the case here. I fact I'm of the opinion they cauterised his character by the end of last year to make the ship fit in.
I admit, Ianto wasn't exactly a shinning example of interesting characterisation at the beginning of season one and, to be honest, he'd reverted to that by the end of the season as well - mainly because he was given next to nothing to do. I liked him in the first few eps, especially when you realised what he was hiding under that very calm and aloof exterior. It was interesting to see such a man going through that and trying so desperately to hold it all together. I was waiting for him to crack under the strain, to fall apart, to hate, to get out all the hurt that Tosh heard about when she was wearing the pendant. But it never happened and by the end of the season he'd ended up virtually the same character he was at the start with the only difference being that it he was shagging Jack. IMO that is shockingly bad, hideous characterisation with no regard at all for the person they'd started to create.
I cannot for the life of me get how they went from:
Episode 4 - Big reveal about girlfriend, girlfriend killed by team mates even though he begs them to help her, boss threatens to kill him, Ianto swears revenge
Episode 6 - Guilt trips everyone about his last kiss being with Lisa (who you killed, you bastards, don't think I've forgotten even though I stay because wtf else have I got?)
Episode 7 - Toss hear emo!Ianto is in pain all the time, just about getting by doing his day to day activities, in a deep period of morning etc
Episode 8 - Shagging the boss....
WTF??? I mean seriously who wrote that as character progression because it completely and utterly sucks. Did he have some kind of emotional colonic at some point between 7 and 8? They had him go through all that pain and angst and bitterness and then just completely ripped it away and went 'move along, nothing to see here, he's all better now'. Or, even worse, they made him suddenly look like he'd forgotten all he'd been through because Jack come on to him and you know, Jack's pretty after all. It just makes Ianto seem shallow and that's certainly not a thing I would have associated with him.
It really does disappoint me that it feels like (especially since they seem to have got all excited over it) that they've almost given up on Ianto being anything other than Jack's lover. He had/has so much more potential. He would have been a brilliant counterpoint with Owen (Owen being the bastard who manages to experience the fuzzy warm feelings of love, and Ianto being the nice sweet guy who gets a massive dark streak because his friends kill his girlfriend and he has no choice but to torture himself everyday in their presence, pretending to be the meek little teaboy). I really failed to believe at all that Ianto would have been affected by Lisa's appearance in ep 13 because he'd seemed to have suddenly forgotten her in ep 8 anyway.
Perhaps they have in mind some deep written psychological issue that to them explains his sudden switch in attitude but if that's the case then they should be putting it on screen, not leaving it up to the viewers to guess. Maybe there's an underlying reason for his playing nice in that he's got some hardcore revenge plot going. To continue the Angel comparisons since RTD's so fond of them himself, kind of like Connor playing all nice and then locking Angel into a coffin and throwing him to the bottom of the sea when he'd gained his trust. If it turns out that Ianto's calm exterior is all a cunning game plan and he's playing them all like fools then I take back all I've said - characterisation was great, never saw it coming, well done.
Jack/Ianto. Tis sweet. It's good characterisation for Jack, to see him in a relationship rather than just a quick shag. So far it doesn't seem to be doing much favours for Ianto though. So please ship fans forgive me but if Ianto sticks two fingers up at the good Captain in episode 13 and then runs off with Captain John having stolen some hardcore alien stuff then I'll do a little cheer. But I will miss his Welsh vowels and nice suits and will hope he gets forgiven and taken back into the fold eventually (I mean Owen shot Jack in the head and instigated near armageddon and he got forgiven so...)