In terms of your dose & free Testosterone, that's unfortunately going to be unique to you when talking about libido.

Libido is one of the more delicate things to deal with when it comes to TRT. If often doesnt take much to over or undershoot the "sweet spot". But there are a few things that play into libido when it comes to TRT. Testosterone, Estrogen, DHT, and SHBG. So interestingly, while Testosterone does have an effect on libido, DHT has a much stronger effect on it. As a reminder, DHT is created from testosterone.

So, one known response that the body will have when you do less frequent injections (higher dose at one time every 2 weeks) is that your body responds by creating more SHBG. It does this because 200mg all at once will raise your levels above the threshold that your body considers to be homeostasis. So your body produces more SHBG in an effort to handle this high load of T all at once. Less frequent, higher dose injections also are more prone to aromatization to estrogen.

SHBG attracts and attaches to DHT at a higher rate than T. So in essence, less frequent injections, as in your previous protocol, is more likely to create more SHBG, lowering your DHT to a greater degree, and also potentially raising estrogen to a level that effects your libido.

TL;DR: DHT has a greater effect on libido than testosterone. DHT has greater binding affinity to SHBG. Less frequent injection frequency means higher loads of T all at once, forcing your liver to respond to this high bolus of T by creating more SHBG in an effort to reduce your free T level, but in so doing, also soaks up a lot of DHT, with the potential of reducing libido.

Frequency may be something for you to look into modifying for your routine.