Even though Mallorca is playing at home and Mallorca is not an easy team to beat, but facing Barcelona it seems Mallorca is difficult to avoid defeat.
Moreover, as you said Barcelona have a much stronger squad this season, and also Barcelona will try hard to play consistently in order to compete
with Real Madrid. So Barcelona will try to win the game against Mallorca, because losing points will make it difficult for Barcelona to win the La Liga
trophy this season. So my prediction is that Barcelona will indeed play attacking and will win the game. What's interesting is that Barcelona's front line
has been very productive this season, when facing a weaker team they will often win the game by a fairly large score. So your prediction that Barcelona
will win by scoring more than 3 goals is very possible.
In this match I agree that this will belong to Barcelona because indeed Mallorca is still quite difficult to steal a win with their current squad which faces Barcelona with a squad that is certainly better. But for the title at the end of the season I don't think they can win at the moment. The league is still quite far away and this can still be said to be the start of the season because it can still be counted on the fingers. Don't forget the current defending champion, Madrid, who still has a good performance so there's no need to be so confident for Barcelona to become champions for now.