I'm new on the drupal forum and need your help quite a big decision.
I'm developping websites under Joomla for 4 years now and I arrive at a point where I always develop my own component (I think it's called module in Drupal) to feat the needs of my clients. Because I prefer to have website realy focused on their need and Joomla component are often full of unneeded features for them and can confuse them. In most case I have to create component to had some fields and change the layout... useless time...
After some research I found that Drupal CCK and architecture is more flexible for my needs but I still have some questions and I hope you can give me your point of view :
1- If I create a new content type on Drupal, is there a way to do some actions before the DB store and before the rendering ? As I use a lot of dynamic forms or other stuff, I use a lot JSON so sometimes I need to make some data treatment before they are store in the DB and before they are render on the page. (If you know Joomla I use Plugin for that).
2- Is it possible to complitely configure the user profile and also by role ? For example Role A and Role B will have different users informations on their profile pages
3- Drupal 8 seams to change a lot of things from Drupal 7 so is it better to wait is release to learn from Drupal as the learning curve will be long
4- I read on forums/blogs that Drupal need more memory than other CMS and I don't undersand why is that a urban legend ?
Thanks for all your help !