Totally agree !
knowing ableton quite well :
to me cubase is 100 times better and faster for handling big projects, finishing projects, mixing and editing, but there is still a few areas where cubase can learn from >
1/ more modularity in the midi and audio insert / processing.
( eg i can not work actually without a plugin host to merge / chain / paralell plugin presets like Image Line Mini Host ( the best ! ) or Blue Cat’s Patchwork - and especially merge and recall different complex config with ease )
Althought the lastest Multitap Delay is clearly heading in the right direction regarding modularity
despite some limitations ( MultiTap Delay : how to set each tap's timing in ms? )
2/ An Easier way of midi assigning controllers to parameters
( NB : i know my way around Remote Devices & Quick Controls 
but still…)
3/ Ability to have other midi inserts than steinberg in the midi inserts slots / without all the routing hassle when loading them as instruments etc.
( anyone struggling with midi divisi ? )
4/ a kind of drum rack host ( 1 midi note = a whole chain ( instruments + inserts etc… ) )
i use kontakt like this, nothing near as easy.
4b/ A possibility to control start and end point of a sample in GA / Sample track / Sample editor with cc for quick editing / choping ( and this is not only for beat, editing foley session, sound design recordings etc… is soooo faster with this )
5/ the docked “channel settings” window in lower zone
+1 for mentioning groove agent wich is a killer as a midi phrase player !
if tempo detection in mediabay was implemented, it could work as a clip player