Cooper has already stated his frustration at the quality of the trialists being offered to him by agents, but a number of players at the club have clearly left the gaffer both pleased and impressed already.
"The boys are really enthusiastic, they are training really hard and I'm really enjoying it," the Gills boss told Teamtalk.
"The likes of Darius Henderson, Danny Spiller and Matthew Jarvis are excellent players. Alan Pouton is great in the middle of the park, and Ian Cox brings plenty of experience to the backline.
"We need to add to the squad of course, but we're looking forward to the season without a doubt."
That news is sure to act as a huge boost to two of those players in particular. Danny Spiller and Alan Pouton found themselves frozen out of the first team last season - and both players, who will have seen Cooper's arrival as a real opportunity to re-establish themselves, will surely be buoyed by Cooper's comments.
After a couple of seasons as a super-sub, Matty Jarvis could be ready for a regular starting place - and Cooper has clearly stated Darius Henderson's importance to the side this season on more than one occasion.
It seems Cooper may already have a fair idea of a number of his first-team starters. With a spine containing Cox in defence, Pouton in midfield and Henderson up front, we look strong through the middle - and with Spiller and Jarvis operating on the flanks, we have plenty of talent in wide areas.
Now all we need is a few new arrivals to bolster the squad and we'll be looking in better shape to hit the ground running, starting at Priestfield on August 6th against Colchester Utd.