Gotze's return to his former employers was confirmed on Thursday ahead of Dortmund's pre-season friendly against Manchester United in Shanghai on Friday.
Tuchel believes the playmaker, who sparked controversy with a shock move to rivals Bayern Munich in 2013, was courageous to opt for a return ahead of what arguably could have been a less complicated move abroad.
"He could have prevented problems by going overseas, but he wanted to come back to us. I see Mario as a central player, I want to see him laugh again more often."
Germany's 2014 FIFA World Cup hero will likely slot into the void left by Henrikh Mkhitaryan's move to United, but Tuchel insists he has no hard feelings ahead of Friday's reunion with the Armenian.
"I am very excited to see him and to give him a hug," he added.
"He is and remains a champion and was a big factor in our outstanding season last year.
"We are not here to take it personally, since it comes down to financial matters and to sporting challenges.
"From my side there are no reservations, although I would have loved it if he would wear a yellow jersey tomorrow."