Hi Kate, another mama muddling along here!
Your DS sounds very similar to mine - quick eater, doesn't do comfort sucking. Never thought I'd be annoyed he usually won't feed to sleep LOL! We also get rooting when he's tired, he's happy to suck his thumb (if he finds it by accident) but won't BF if not hungry. We don't use one (personal preference) but have you tried a paci to see if he'll take that?
In terms of routine, well we don't really have one either except for trying to establish some sort of BT routine. I think where I drove myself mad with DD was trying to fix everything all at once, and expecting to get a textbook routine early on. To be honest we don't have much rhythm to our days yet, though nights are pretty good (sleep by 7/7.30, feeds at around midnight and 3am then WU 6am ish). I'm not sure I'd spot any patterns yet even if I tried to, because so much is dependent on what we're doing, where we are (eg the long naps in car or sling which would have been short if at home) - although I think Tracy's advice was to do as you've suggested and keep track of things for a few days.
The way I'm trying to think of it is to work on one thing at a time. My "list" at the moment is establishing a BT routine (we are doing bath, feed, bed after DD is in bed), trying to get a rough 3 hourly routine for feeds, trying to learn and respond to sleep cues (variable success) and trying to get a bit of A after each E. So much of me wants to get it "right" this time but I'm trying to remember that it's a journey, not a destination. Not sure if that helps, but setting small goals at this age seems to be a good place to start.