In my view it seems clear that they have made some good improvements, the time they achieved in Q1 with Alonso was a bit of a surprise. I know there was quite a bit of track evolution and others maybe not getting their best laps in but it was encouraging.. At least Jenson got to the end of the race! that's more data than they got on most days last year.
If we believe their press releases and what people are saying from the team (which is hard to do given last years Bull Sh**). They have allot of progress they can make just by running the engine and changing maps, they have had limited running with the new spec engine and one can only hope that given its young age compared to other engine manufacturers there is allot more untapped potential even without Hardware updates (remember Mercedes have 4 teams of Data, Ferrari have 4 teams data(not sure how many of them have 2016 power unit??), Renault have 2 teams data Honda have 1.) so the understanding of the engine compared to the others is low.
What I do think is now clear is that the Honda Power Unit is better than the Renault engine in its current form, and look what Red Bull managed to do. Leaves me to think that McLaren Chassis aint great! (no wonder McLaren didn't want Honda to provide Red Bull with a engine.)
On another note, Alonso's engine. Im assuming that is now a goner so he will be on his second engine already. May mean that if any upgrades were going to come over the next few races, then Alonso may well not get them as it will mean introducing yet another engine.