I would miss the in-order collects, actually collect/maximize/... features, destructuring of lists, direct type declarations, ...
I also find DO not easy to read and understand.
The code from above I would actually write in LOOP as
(loop for a from 1 upto 5
and b = 10 then (* b 1.5)
collect (* a b) into c
finally (return (list a b c)))
Of course to each their own. I like LOOP a lot actually when I need to do something familiar, however for something unfamiliar DO is often my choice. It also serves as a caution to tread and think carefully when I return to the code. Sometimes, after a while, I realise how to do the DO construct succintly with LOOP