Watford completed loan deals for Barcelona forward Gerard Deulofeu - who played 88 minutes against Stoke on Wednesday - and Sunderland's Didier Ndong in the closing days of the window. Dodi Lukebakio also arrived at Vicarage Road after he completed a permanent switch from Anderlecht.
"We now have three new players in positions where we needed to improve," Gracia said.
"I am confident they will give us good results with good performances and good games.
"Ndong is a position where we needed to have more possibilities. Lukebakio can play either side of midfield and Gerard is also a player that can play on the right and left and with good quality to attack.
"The players are with us now and we are very happy to have got them. I hope they will be better for the club and that is all I am focused about."
Following the signings of Gerard Deulofeu and Didier Ndong, the number of overseas players rose to 18 and only a maximum of 17 are allowed in the 25-man squad.
Signed on loan from Udinese, the Mali international has made a total of seven appearances this season and the Hornets have stated he will remain at Vicarage Road to continue his recovery from a hamstring injury.