Having your own system is great. This does, however, not mean that you should stop looking for new opportunities and testing other systems. On the contrary, try as many new systems as possible and look for what works best in specific situations. Keeping to one system is not productive.
3. It requires a lot of time
Managers often do not change their unproductive habits because they think that they do not have enough time to do it. They imagine that it would take all day or even several days to adopt a new time management system. That is not true. You only need to move in small steps. You can start with finding a little time to think without being distracted every day.
4. It is up to you
For the most part, it really depends on how productive you can be. There is always pressure on you to complete certain tasks early and there might really not be space for quiet reflection. This can be caused by obstacles beyond your control such as unclear strategies and processes. Then it's up to you to ask why things are not done more productively.
-kk-