I don't think this is working too well as a collaborative game, so I suggest we try the competitive version: try to come up with as long a string of words as possible, all by yourself. Refinements of previous strings are fine, just try to get it as long as possible. Once again, the original rules were that you may ADD or REMOVE a letter, but not change letters.
For example, here's my first try, after a bit of tinkering:
a an and hand had hard shard shared sheared seared speared spared spare spar spa spas spars spares pares pare are fare far fear fears ears ear bear bar bars boars boar boa boat bat bath bathe bather bathers bathes baths bats brats brat rat rant ran rain train strain stain stains strains trains rains brains brain bran bra bras
(59, if I've counted right)