Pintassilgo gave Arouca the lead at home on Monday with a swerving strike from the edge of the area but Kuca's sharp finish just after the half-hour mark dragged Estoril level by half-time.
The visitors had the better chances to win the game in the second half but two fine saves from Arouca's Goicoechea ensured both teams picked up a point from the 1-1 draw.
Arouca moved into ninth position in the standings, two points behind leaders Sporting Braga at the end of the first round, while Estoril are in 10th.
In a first half with plenty of goal-scoring opportunities, Arouca hit the front on the counter-attack with Pintassilgo taking advantage of some sloppy defending in the 16th minute, before crunching a half-volley past Estoril keeper Vagner.
Estoril had the majority of the chances, however, finishing the game with 11 shots to Arouca's four, and the visitors deservedly levelled the match in the 31st minute.
Kuca played a one-two with Toze, who was busy throughout, and the Cape Verde striker converted smartly from inside the box.
After the break, Seba and Toze both failed to score from one-on-ones against Goicoechea, while the former had a late 25-yard free-kick saved as well.