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