On the opposite side of the specter is Astarion - the only way to romance him is to be rude, dismissive, and aggressive towards potential quest-givers. Which a) does not make sense (he is a vampire, hiding his nature, who is also well bred and knows how to behave), b) harmful to the play-through, since you simply loose some quests. I can add c) you have to go the evil route, but that can be seeing as a good thing.
I don't think I have missed out on any quests while romancing Astarion - though my character started off as Good (how I normally play) then veered sharply into Chaotic Neutral just to please him. :P You don't have to get ALL of his approval points, probably just the major plot ones relating to him directly (bite scene etc). I did as much of the content as I could though, helped everyone before getting to the Rescue Halsin from the Goblin Camp, so that the overall incremental approvals probably added up. I still took quests and helped people, just had to sound a bit snarky about it.
Shadowheart disapproved of my actions ALL THE TIME, so it was a complete shock to me that at Medium reputation she propositioned me at the party scene. I don't even know how I got to Medium reputation with her in the first place! I told her no thanks, because I was about to pounce on Astarion, and of course she disapproved. :P But what I'm saying is, you can still play however you want and the romances are still mostly recoverable. All of the characters are complicated personalities with various proverbial (and probably literal) skeletons in their closets, so as long as you also play a little bit complicated, not a straightforward 100% goody-two-shoes path, they'll still fall in love with you.
There are no alternative pathways even for the easier romances - you missed a scene because of pressing on with exploring, you are locked out of the further content.
This is the bit that definitely needs fixing, I agree. My husband missed quite a few of the camp scenes with companions on his first playthrough because he didn't realise there was no penalty for camping early and often! The characters are all like "there's no time to waste, we need to find a healer" so he delayed long rests at camp for as long as possible, skipped a bunch of cutscenes, and without the forums wouldn't have even realised this. The cutscenes definitely need to be queued up and happen in the order they were designed to be experienced, rather than ending up being completely missed. Otherwise a lot of players will also take the characters at their word, avoid going to camp often, and miss the best character development.
