does this look doable?
In terms of A time and S times, if this was your routine it would be lovely. In terms of doable, possible, hmm..don't know about your LO but mine would not just move his morning Wu time by half an hour if I wanted him to move his routine, it would be a huge struggle, in fact I struggled for a long time with early mornings and being unable to move him to a reasonable WU time and that was with a pretty good routine and independent sleeper. If you feel you can get that Wu time to 7.30 and start your day there - great.
If not you might need to re-think or put in some hard work to get it there.
I would put that 6pm feed later, just before BT. If necessary put in a cluster/top up feed so one after the nap and another before BT.
What would I see if she's getting overtired?
Grouchy, crying when waking, often sudden wake ups from the nap at 10 or 20 mins.
Honestly though if you can cope with it, the fastest way to get onto a new routine is to stick to the times and eventually your LO will sleep. The OT helps to set the new routine up so although we generally avoid OT in our day to day routines, when implementing a new routine it can work in your favour.