Newcastle can't be competitive for the Champions League much for now. Maybe they are one of the richest teams in Europe but they still can't make their squad one of the bests yet. It isn't an easy task to convince big names into their squad despite qualifying for the Champions League. They need to maintain consistency in the Premier League first.
Once they convince bigger names with their performance then they will able to bring that kind of players easier. Those players are already playing for top teams in the end. Newcastle will need to give them a reason why to join them instead.
For a while we can't confirm how far Newcastle's performance is in the Champions League and also in the Premier League, for sure the competition last season is not the same as this season as we know some clubs have increased their squad then we have to see at the start of the season. In the pre-season matches, Newcastle's performance has been very good so far they haven't lost in the last 6 matches however, these good results cannot be used as a benchmark for their performance.
If we check the Premier League schedule in week 2 Newcastle must face the strongest club Manchester City as an away match, in this match we can see how far their squad has improved of course it's not easy to get points against Manchester City, there are 2 choices lose or draw.