Sean Dell - it is very difficult to provide a constructive answer to your question without knowing the full facts of the situation ie:-
Was the aircraft in front a light vortex wake category and therefore subject to a 2 minute delay behind you which would not apply the other way round?
Were there 3 aircraft looking ready to depart with one either side of the second one? This would give a much longer delay all round if the one ahead of you was delayed.
Was there a slot time to take into account? Not even necessarily for either of you.....
Was there landing traffic waiting to pass through the apron?
Was there landing traffic waiting for the stands that one or both of you were occupying?
Was there landing traffic that would affect the way in which you both got airborne? If the aircraft ahead generally is quicker to get airborne then a smaller gap that couldn't be used by you could be used by him.
Was there a third or fourth aircraft to take into account?
Did the tower controller end up with the same situation the day before, do it the other way round and the same aircraft with a different crew took forever to taxy off therefore unnecessarily delaying the other one?
As to the speed restriction and multiple heading changes are you entirely sure they were due to the aircraft departing ahead of you? They could also have been applied due to, for example, separating you from inbound traffic from Brest to either Jersey or Guernsey, separating you from inbound traffic to Guernsey or Jersey through ORTAC, separating you from traffic departing Cherbourg towards ORTAC.
The speed restriction is not that usual (although valid) but although may have been given by the Jersey Zone controller it may have been on the instruction of an en-route controller due to delays into an individual airfield or through a particular reporting point.
There are many, many variables to take into account in any situation and ATC in general will try and provide a solution that provides the safest most expeditious solution for
everyone.
If you would like to learn more about it most air traffic units welcome visits and comments from crew in order that we all learn from each other.