I don't see how the lack of (IMO) optional parens would prevent tools from working - they'd just have to be adjusted. Assuming this example from the ParEdit page is well-formed lisp:

    (defun paredit-barf-all-the-way-forward ()
        (interactive)
        (paredit-split-sexp)
        (paredit-forward-down)
        (paredit-splice-sexp)
        (if (eolp) (delete-horizontal-space)))

It doesn't seem that hard to rework a tool to use sig whitespace as indicating parens to have it operate the same over this code:

    defun paredit-barf-all-the-way-forward ()
        interactive
        paredit-split-sexp
        paredit-forward-down
        paredit-splice-sexp
        if (eolp) (delete-horizontal-space)