One rather small (relatively other features, as I imagine), but an incredibly useful improvement was described in Columnstore Indexes – part 109 (“Trivial Plans in SQL Server 2017”) – is the ability to automatically produce Fully Optimised execution plans for the Database, which compatibility level is set to 140.
Running on both instances (Standard & Express), the following script, while altering the compatibility level between 140 (SQL Server 2017) & 130 (SQL Server 2016), will produce different execution plan for the SELECT COUNT_BIG(*) operation – the fast one (with FULL optimisation in 140 compatibility level) and slow one (with TRIVIAL optimisation in 130 compatibility level):
I am happy that this feature has got no Edition dependence, this is a needed improvement that simply increases the value of the offer and can actually be achieved in a lot of different ways, event without parallelism kicking in.
Niko has also helpfully provided a table at the end of the post to summarize his findings.