IMHO Get the IR FIRST!
Cpl without IR (assuming UK based) means no commercial work and therefore no income!. Commercial pilots fly in cloud! Alot!
CPL/IR then the decision...... FI????? Well everyones route to the front seat is different but..... I had the same chioce some 5 years ago. Postponed my FI course (got the jitters) and went hunting Piston commercial work. Fell through but landed a job parachute dropping. Left this with just over 300hr total and joined a regional airline on turboprops.
Now a captain of a 20Tonne plus Turboprop flying schedule and charter over UK and Europe.
All the best, It's not cheap, but you knew that when you started??