As a matter of interest I think if my control systems had so much slack as suggested I would ish to have all control linkages checked or am I being over cautious
Slack probably needs to be defined a little more. What one interprets in the cockpit as "slack" can mean a lot of things. If it's play between the control yokes, there's not a lot that can be done, within certain limits. If it's play between the control in the cockpit and the control surface on the wing or stabs, then it's a big concern.
Taking up "slack" is a lot more than checking linkages. It's checking cables, turnbuckles, pulleys, bellcranks, and particularly cable tensions, as well as overall rigging.
You will notice a certain amount of play in rod ends and other points in the system, which can only be removed by replacing those components. A certain amount of play is acceptable, but not much.
You're not being overly cautious. If you have any concerns at all, you should have it checked over by a qualified mechanic.
Although we'd set them up to the book some owners liked them adjusted down a bit - as is said "adds a bit of lift" - at lower speeds I'd assume. As long as it was recorded in the Log Book this was acceptable (then).
Control rigging is a critical issue, and the rule now, as it has always been, is that it must be done in accordance with the manufacturer specifications or as ammended (eg, supplemental type certificate, etc).
An old mechanic's trick for an airplane out of trim laterally is to rig a flap low to "pick up" the wing. This is really poor practice for addressing the symptoms, and not the problem.