Originally Posted by Wilfred Laurier

for a different riding experience
consider changing the handlebars to a different shape
or
converting to single speed
or
assuming your miele has 700c or 27 inch wheels now
investigate the possibility of a smaller wheel diaeter
like 650b
which could give you the ability to run fatter tires
and ride off road

but simply going from
bike 'a' with x speeds
to
bike 'a' with x-y speeds
will make very little practical difference while riding