I agree, and work in the same way, by programming my own tools. But I do
think the opposite view is totally valid: tools that have a lot of
funtionality out-of-the-box and a good interface, make it easier and faster
to finish art.
I understand the need for personalized tools. Like many people, I feel that
my ideas are not possible with off-the-shelf tools. But I also sort-of
resent the time + effort required to make these tools, and sometimes feel
the time + effort would be better spent on art-making.