I feel obliged to mention doas[1], which is a sudo alternative from openBSD. It is written in c, but tries to be smaller and easier to configure. I am not qualified to vouch for or against it, but it is interesting.
OpenBSD has maintained exceptionally good taste when it comes to change. When they rip out and replace a "classic" utility, they invariably make a modern classic: openssh, pf, doas
When others rip out a system and replace wholesale, they often just do the hard work to secure the existing thing: Wayland vs. Xenocara
I don't know that there's any objective way to know ahead of time whether replacement or repair is the right approach. But the fact that such a relatively small project such as OpenBSD has managed such outsized positive impact across the open source landscape speaks volumes to their intuitions here.
(aoeu)id(htns)
# Toggle "doas" at the start.
toggle-doas() {
[[ "${BUFFER:0:4}" = "doas" ]] &&
{CURSOR+=-5; BUFFER="${BUFFER:5}";} ||
{BUFFER="doas $BUFFER"; CURSOR+=5;}
}
zle -N toggle-doas toggle-doas && bindkey '^s' toggle-doas