We've managed to get over to daddy's work in Canary Wharf quite a few times now. It has been one of the more easier parts of London that we have been able to access on the underground, helped greatly by being able to get from Brixton to Canary wharf pretty much step free due to the lifts and level access platforms with only the one change at Green Park.
Usually if we're out and about with CS in the push chair, I need to add on about half an hour to our journeys to include additional changes or taking the chair up/down stairs (I've yet not to be approached by people offering to help with stairs) so being able to do the usual route to Canary wharf has been great.
Usually we end up meeting Daddy at Boisdales, which is a Scottish/french bar and jazz restaurant which also has an outdoor terrace area, we've ate here a few times (before and after CS arrival) and until Christmas the menu was great however on our last visit the menu in the bar and terrace had changed (when we asked the waiter her just said it had been changed a few months before) and didn't have the same selection as before. Although there isn't a baby changing area (which i find a bit odd but c'est la vie) there has been a few more families eating whilst we were there.

Cabot place which is part of the shopping complex at Canada square in Canary wharf, the staff in Canada square its self are extremely helpful and seem to enjoy cooing over babies! On one occasion when I made the journey myself (and got lost trying to find a lift) one of the concierge staff made sure that I got to a lift, and stayed there until I got to the floor I needed - the lift was one of those ones that you need to keep the button pushed - and when I passed later the same member of staff was helping another mum to find somewhere comfy to sit so that they could breastfeed their baby.
As a new mum I was still finding my feet about feeding CS in public (not helped by being uncomfortable by some people and this making me feel over anxious and stressed on one of my first outings) but I generally prefer to settle down in a cafe or restaurant rather than on a bench or in a changing room and in Cabot place Costa Coffee,on the Mall -1 level of Cabot place, has often been my go to place.
Plenty of space to manoeuvre CS chair, comfy booth and arm chair style seats and yummy decaffeinated latte's (finding decent decaffeinated coffee since CS came into our lives was a big thing!) the costa is also opposite the toilets and baby changing rooms (there are 4 separate changing rooms on the floor) but there are toilets and changing rooms available in Costa too.
The Changing room (in Cabot place not costa coffee though there is one there too) has plenty of space for CS push chair (admittedly his isn't that big) and also has a vending machine for nappies and wipes incase of an emergency!
Its pretty clean (not surprising for Canary Wharf) with my only issue being that even though there is a sign on the lock saying engaged when you've locked it you still have the regular person trying to open the door (a big pet hate of mine particularly when there is an obvious engaged sign and especially when you've only just got in), along with some people ignoring that there are other parents waiting to use the room.
It also appears to be (along with the accessible toilet next to it) used as a quick option for anyone to use rather than than walking round to the actual toilets
The scores on the doors .....
for Cabot Place changing rooms
5/5 access - very accessible, plenty of lifts and level access or ramps to access the main building
5/5 cleanliness - from what I saw the toilets are checked regularly on an hourly basis
1/5 comfort for feeding - only sitting place is the toilet itself which at least has a lid/cover
5/5 helpfulness of staff
1/5 cost - expensive if you need to buy their vending machine nappies/wipes!
Total: 16/25
for Boisdales Canary Wharf
3/5 access - lift access to both bar/terrace and restaurant however no baby changing facilities so you would need to use the cabot place ones
5/5 cleanliness
3/5 comfort for feeding - most of chairs are standard wooden ones with no arms but still comfy enough, no issues whilst breast feeding
4/5 helpfulness of staff - happy to move tables/chairs to fit push chair in restaurant and on terrace
3/5 cost - pretty much usual cost
3/5 food - would have been higher but the menu isn't what it used to be
Total: 21/30
for Costa Coffee Cabot Place
5/5 access - Its opposite the baby changing / toilets and is level access throughout
4/5 cleanliness
4/5 comfort for feeding - option of booth style or arm chairs which provide convenient and comfy cover, no issues breastfeeding (even a few complimentary comments!)
4/5 helpfulness of staff - happy to bring drinks and food to where you are so that you aren't balancing a tray whilst pushing chair
3/5 cost - standard costs, really comes down to
3/5 food - usual cakes and savouries
Total: 23/30