Fifilottie, I started to introduce a bedtime routine from around 8 weeks and I have found that being consistent really works...DD is 14w now and consistently sleeps 9pm - 5am.
We are first time parents and initially thought we were doing the right thing by keeping DD downstairs with us in the evenings until we went up to bed. She was extremely fussy in the evenings and we would pass her back and forth between us trying to keep her happy. I too was feeding her to sleep, but she would wake again at very short intervals. I eventually thought that maybe she actually needed to go to bed (actually it was a friend with a slightly older DD that suggested it) and so we implemented a routine. From the first night, she went to sleep herself (albeit with lots of patting/shushing etc) and slept for 8 hours solid!
We don't wake her for dream feeds as she sleeps through until 5am herself and if she is hungry earlier, she wakes me up to let me know, but generally I try to make sure she has plenty of feeds in the day to make sure she's had enough calories. DD is EBF and has never had a formula top-up (in fact she point-blank refuses a bottle and will only except the real thing!) Her weight gain is fine.
IME if you persevere with helping her to settle herself, obviously without leaving her to cry, then she will get there. I disagree that it's too early for sleep cues to work. DD seems to know that when she has bath/wash, feed, put into sleeping bag, cuddle, then it's time for sleep. I have also got a really cute soother 'blankie' thing from Boots which I tuck down my bra/top to make sure it smells of me, and she sleeps with it right next to her head - in fact she now snuggles up to it!
I do find that sometimes DD likes to have a shout and a moan just before droping off, it's not so much crying, but must be her way of releasing all her stress/energy before drifting off. It took me a while ro realise the difference between this and her really being upset.
Sorry to waffle on, but hope some of that helps