About Cullen showing leadership skills--well he wasn't given much chance to, was he? Every time we have met him, he has been under the orders of someone else. As I said in another thread, my little dalish elf had none either. She was happy with Tamlen, just hunting and whatever else elves do in the woods. However, Duncan saw something in her (perhaps much like Cassandra sees something in Cullen) and she soon rose to the challenge of saving the Circle, placing a Dwarven king on a throne, uniting an entire country under her cause, winning a Landsmeet, placing another king on the throne and being personally chosen to lead his armies against the darkspawn, among other things. She did okay for not having any leadership skills. Cullen has military training and is a warrior. He is also trained in killing demons--which is good, considering they're going to be oodles of them about. As far as I know, and as I have stated previously, his duties will be to advise you in military tactics and strategies. He is qualified to do so.
Also, doesn't he tell you he'll pass the information about Anders onward if you warn him? How do you know he doesn't? As for why he was insubordinate to Meredith, I guess that could be left to interpretation, but I doubt it was born from fear. He always seemed duty bound, arresting Hawke for a trial was one thing, outright killing him was another.
You see, I have different point of view while we are talking about PC/NPCs in games and theirs role. For me, PC is a sketch from Devs Im filling. Of course, for example, there are mistakes in DA:O made by Devs, like Dalish Elf decision about who should rule Thedas ( while we all know what humans are thinking about elves, why for god sake they are asking my Dalish Warden,, who really don't care), but still a big part of player character is a head canon, and in this way PC will be reliable on almost every position game put him/her on. From other hand, NPC is created by Devs as a whole. So here, facts we are given by Devs in game/games must make character reliable in his/her role. As I said before, I, as a player, know Cullen only from two previous games. You said he was trained as a Templar, deamon-killer and I agree here. But training don't make someone a champion. The fact, that I was teached how to paint don't make me Michael Angelo or DaVinci right? Cullen will be Military Adviser and according to BB interview he will lead Inquisition's troops. For me, someone on Military Adviser position have to be experienced on a battlefields, and knows tactic not only in theory. Instead, knowing facts only from two other games ( no head-canon, fan-fiction or wishes about Cullen in DA:I), I see a young man, who spend almost whole life locked in a Circle Tower, hated mages ( I know he was tortured by them and I even understand him),, blindly followed Meredith, never participle in serious, big battles ( those in Kirkwall weren't too big tbh),and never was on leader position,.I never saw him as a leader, never heard in games about his succes on a battlefields, the only think I knew after DA:O was that he murdered three young mages, that's all So, for me, BioWare failed here by theirs creation of Cullen's character, and they don't convice me, that he is right person on a right place. Of course, in October, when I will know the way BioWare re-created Cullen in DA:I , I can change my mind. Hope it will be handled better than in ME3 , when Kaidan was a SPECTRE just like that, without really good reason ( well I suspect that Udina had a hope that Kaidan will be more loyal to him after that) Anyway it's good to be able talks here without being called a " hater" only becouse I have different pov. Thanks.