Sure, but Ten Hag is not like Xabi. I think he has a different technique. So it's not necessarily that Ten Hag can cultivate Xabi's legacy well. It's still difficult to guess from the beginning. I think the playing pattern and technique will be much different from Xabi. History in the EPL proves, even he is not able to compete with other teams when he already has the players he wants. The league conditions are different, but I don't think he'll be much different. I think the dominance of Dortmund and Munich is still very difficult to eliminate for next season.
Erik ten Hag doesn't need to focus on winning the Bundesliga in his first season at Leverkusen, the only required result is for him to keep them in the Champions League and give them a good ending in the title run. For a change of pattern, it will be a different game style, two manager will always find it difficult to cope using the same formations, now that the club is losing and gaining players, it will all be about Erik ten Hag, Xabi did his own time now he is out and everything changes.
It will be very difficult for ten hang to win the bundesliga title with Leverkusen in this his first season I don't even see that happening in his second season because ten hang playing pattern and that of Xabi is s different ten hang should focus doing well in European competitions while building a new team and strengthening areas that are lacking in the team left by Xavi Alonso.
The bundesliga has by dominated by bayern munich and with the squad depth that bayern munich has currently it will take a miracle for Leverkusen to come and win the league title in Germany