"It's a shovel, dig a hole."
"It's a hammer, hit the nail."
"It's a putter, stroke the ball where it needs to go."
Yes, comfort and balance and an easy mind are far more important than the tool. Of course you want to avoid "suck-ass" designs, which have been pouring out of pretentious putter manufacturers for the past 10-15 years now -- such an awful lot of crap putters the world has never seen before!!! Gagg. Stupid designs, really wretched junk.
Putter features DO NOT HELP, despite what the manufacturers claim. Scotty Cameron putters have ZERO helpfulness in the design and quite a bit of bad physics in them. Just ask Chad Campbell why he doesn't have a green jacket after his Scotty Cameron putter screwed his golf career on a 4-footer in the playoff against Kenny perry and Angel Cabrerra -- junk physics made for bad greens that haven't existed since 1980 that fanned open in Chad's West Texas "sensitive grip" and cost him all the previous 20 years of hard work. Zeroed out his life, really.
The SCIENCE knows that putter features sold by manufacturers DO NOT HELP. Stop believing that they help. "True-roll" putters don't help. Heel-toe weighting schemes don't help. Big-headed MOI designs don't help. Aiming marks concocted by a glasses fitter / optometrist don't help. Big-ass grips don't help. Backweighting plugs don't help.
Try reading this book on the science of putter features:
Frank D. Werner & Richard C. Grieg, How Golf Clubs Really Work and How to Optimize Their Design (Jackson, WY: Origins, 2000)
Paperback, 183 pp., $29.95. This is a physics book for golf club design, and half the book is devoted to an analysis of putter design physics. The authors derive empirical formulae from numerous laboratory and on-course investigations / data-gathering. The authors convincingly debunk much modern dogma about putter designs, proving that a standard putter from yesteryear is probably just as effective as one of the greatly overpriced specimens touted nowadays as "must-have". Practically no design features in putters matter much, with the exception of aiming aids. When all is said and done, it comes down to square contact with a squarely aimed face moving squarely at the target.
What helps is this: an appropriate overall heft for your body and tempo and usual green speeds; not excessive loft; a good length and lie that promotes comfort and balance in the stance; a grip that is not too thin and not too thick that fills the hand and does not call attention to itself; and a plain putter head shape and appearance that allows aiming the tool without careful watching and scanning the shape for its odd angles and corners and contrasts checking to make sure this weirdness or that weirdness isn't going to cause something funny -- just a plain unadorned tool that leaves it up to the golfer to aim and swing. Nothing else is helpful. All the "special" features is like trying to run the 440 race wearing a one-man-band outfit.
You might be able to make some sort of music, but you're probably not going to be able to dance all that gracefully!
Putting Coach and Theorist