I personally think limb weight is over-rated to some degree... Of course you don't want grossly over weighted limbs and slim and narrow as a general rule will always be faster... I also feel that some of those older recurves with wide limbs, especially near the tips, whatever they gained in performance of recurving the limbs they lost some performance by being so wide...
To prove my point about being over-rated, I was taking most of my limbs down to around 7 /16"... I was never really comfortable with such a narrow limb... Just looks a little on the frail side to me but I thought it is the way to go for performance... One day I made a R/D bow that was shooting 187 fps... The tips were rough sanded just a hair over 1/2"... I said to myself, "Boy, wait til I take these limbs down to 7/16", this puppy is gonna scream".... I did it and the bow went down to 184 fps... End of story... There are such subtleties in limb shape that you can't even see unless you map out the limbs and compare the way they bend... I keep kicking myself for not mapping out those limbs...
Now I make my bows a 1/2" at the tips... They look much nicer and stronger to me and I am not really losing any performance...
*** This was my experience... Yours could be different when it comes to design and materials used... No matter what anyone tells you, you should never take it as written in stone... Take that info, store it, use it as a guideline or reference but you always have to find your own path... ***