Does having multiple view filters affect the overall performance of the site. for example having a category and search filter on main pages of articles and galleries?
In general having more views will effect the performance of your site. However you can check the view query / render etc at the bottom of the view edit pages which should give you insights into what degree they effect performance. You can also cache views but it means there will be a lag on content updates being shown by the view.
In general you will also find more modules you add to drupal will have a performance impact although it could be slight. Even adding views to pages will add js and css and thus the more page weight so it will take longer to download. Also views run will have more db queries and have a performance impact on the database.
Was there something in particular you were looking for?