Views of views, complexity and speed.

 Hello list.

 I have a question about complexity of queries and performance. I only
 look for qualified opinions and comments.

 In my database I have a pool of tables and views with rules for
 inserting, updating and deleting.

 In order to avoid complexity, some views looks in other views and
 join them for getting data.

 I see queries against that views result slower than queries against
 plane tables or simple views by an order of magnitude (when not two).

 My question is: if I would make complex views looking in plain tables
 instead of other views, could I gain speed with the cost of more
 difficult maintainability and readability?

 Sorry for lazy data and arguments. If any of you think that detailed
 tables and views may help, i can send them without problem.

 Thanks for any opinion.

                             David