Yes, Aston Villa has indeed experienced very significant progress this season and this cannot be separated from the hard work of Unai Emery who was able to make the club compete among the big Premier League clubs. But the strength that Aston Villa currently has is not playing games even though the depth of the squad they lost to Arsenal and Manchester City but in reality Aston Villa were able to beat them. This was not just luck because they also fought hard to be able to beat these top clubs, from a financial perspective I agree that Aston Villa does not have the finances of a top club.
Aston Villa's defense, I admit, they maintain a very tight defense, but sometimes Aston Villa starts to lose concentration if they start to concede, like in the match against Manchester United, where initially Aston Villa took the lead in the first half, but Manchester United was able to provide a counterattack which made Astin Villa lose focused in the second half until finally losing. This must be a lesson for Aston Villa so as not to lose focused when have conceded to the opposing club.
Well their lack of concentration in games especially when having 2 goals up is usually what affects this team. Like in the game against Man United, they lost concentration and this had a negative effect on them. They lost all 3 points and even struggled not to concede more than 3 and this is what they should try to work on as a team, else they'll miss their chance of qualifying for the top four to participate in the UCL tournament season.