Clark was disappointed by the failure to beat Blackburn after the home side finished their npower Championship season with a 1-1 draw but believes he has a good basis for the future.
He said: "I am looking to bring in young players and carry three or four senior players next season in terms of age and experience as it is important you have those type of players."
On-loan Ravel Morrison gave Birmingham the lead in the 42nd minute but Jordan Rhodes came to Blackburn's rescue with a 66th-minute equaliser.
Clark admitted: "It looked like an end of season game which makes me a little unhappy as it shouldn't be like that. It was frustrating.
"I keep telling the young players that when you slow the ball down you give defenders a chance. If you run quick they struggle to stay with you. If we had done things right we could have put the game to bed in the first half. We have better standards.
"The way we have finished has been encouraging. I am looking forward to the summer. It is going to be busy and I am looking forward to building a young vibrant squad.
"No transfer fees will be paid. The budget will not be anywhere near where it was so players coming in will not be getting the same salaries as they have in the past."
Blackburn caretaker manager Gary Bowyer was relieved to have finished the season in 17th spot following a traumatic campaign at Ewood Park.
He admitted: "We were poor in the first half as we didn't play to the tempo and intensity as we have done over the last couple of weeks. I thought it was very much end of season but in the second half we deserved a goal and we might have nicked the game."