Doing well in the exams is important. Ideally no retakes, not less than 85% in any exam and really a very good mark in Navigation. Demonstrates your brain may well be wired up correctly as an aviator.
First time passes in the flying is very advantageous !
Once your ATPL is issued, your initial training record normally becomes less important as experience is gained.
Getting on that first rung is the most difficult bit.