Of eight special delimiter character you list, three are used for macros. While the syntax of the highly evolved Common Lisp you have in mind remains extremely frugal, macros are only one of many relatively large unnecessary luxury feature.

Teaching fancy language features in an introductory course steals time and attention from fundamental functional programming principles. CLOS, unless thoroughly dissected as an advanced example of how far can you go with LISP, would be an even worse gratuitous distraction than macros.

Of course, "complex" LISP isn't going to be comparable with Haskell, and in a sufficiently long introductory course advanced language features might be worth teaching to increase student productivity.