And by the way MNs come in many flavors. The 38s are not at all heavy, and to my estimation neither are the 91-30s. Enfolds, 98 Mausers, and Sprinfields are all heavier. A sporterized MN is quite light.
Most MN are not too heavy for men, can be heavy for women. Yes you can do a lot to trick out the MN. There is even an outfit that sells a bullpup replacement stock.