Technique is a key element and possibly the most important element to any improvement in strength.
Training with poor posture and/or incorrect technique can lead to a slower development of kicks and esquivas, and may also result in injury (e.g. lower back pain, muscular strains, etc.)
During capoeira training, maintaining a proper ginga and cadeira position during sequences will strengthen your leg and core muscles, and will improve your general stability and endurance as it is essentially a half squat and half lunge.
As your basic ginga and cadeira technique improves, lower your stance and maintain throughout to add more tension to the leg muscles, making sure that you contract your core muscles to minimise the risk of lower back pain.
When you focus on doing the proper technique for even a basic ginga and cadeira, other aspects of your capoeira training will improve.