The Wildcats finished the regular Super League campaign as the form team with seven straight wins to pip Bradford for the last play-off spot, but their season was brought to an end on Saturday night when they went down 42-20 in their elimination tie at Leeds.
Agar said: "The challenge for us and for me in particular is to make sure we can move forward next year and I'm looking forward to that. I think we defied lot of critics this year but, as sure as eggs is eggs, it will only take a couple of losses for someone to tell us it was a flash in the pan."
Agar inherited a side from John Kear that finished second from bottom of the table in 2011 and virtually rebuilt the squad with no fewer than 18 signings for the start of his first season.
He now intends to keep the bulk of the team intact and make a couple of forward additions to ensure that this year's progress is maintained.
Agar added: "I don't think we need too many new faces. I certainly think we need a bit more firepower up front, an ability to hold the middle of the field a bit better defensively.
"We've got a lot already in place and it would be wrong of me to try to change that too much.
"We've got to build on it and try to add if we can add a bit more punch in the middle so that we can hold our own against other packs on a more consistent basis."
Agar's priority will be to secure the services of goalkicking stand-off Paul Sykes and prop forward Kyle Amor, who have both been big hits since joining the club on loan from Bradford and Leeds respectively.
The Wildcats have also been linked with moves for Scott Murrell (Hull KR) and Ian Kirke (Leeds).