hi,
two different things here
- the "last" issue is not really one as you can tell wayfinder to use another classname for its last items or use yourself another one for you search extra element, wayfinder's one may still be useful for you to style the last element of a dropdown (no bottom border for ex)
- the other issue is if you really want to add extra elements between wayfinder generated li (if it just some decoration js would do the trick)
-- you may put those element as weblinks or else in your site tree
-- or write a snippet to generate your menu using modx api, really easy in evo (don't know in revo but, as i may still have some usage of my family jewels i'm not going to give any opinion about this here, let's say it will be even easier

)
have swing