I wouldn't really call 2 games experienced and my opponent had only a few more games. More observations from major Bigglesworth diary on a successful foray. I had 5 bearers with an explorer and 2 hunters with hunting rifles. My opponent had british rifles. The bearers ran ahead using cover (their speed of 2 gives a good distance or negated most terrain penalties) and tried to gang up on individuals on the edges. You asked about closing, they were doing 11" a turn (6" base + 2" speed + 3" run). They were on the first rifleman by turn 2 or 3 for no losses.
Rather than being gunned down by the rifles in best cinema tradition, what I found was if the opponents rifles moved, then most couldn't hit the bearers. If the rifles stayed still it was still hard to hit the bearers with cover bonus and run bonus, and they became sitting ducks for the hunters who were out of their military rifles range. The hunters could also fire into melee without hitting the bearers. I'm sure some of the samurai could have the hunting skill to provide similar cover with bows. The rifles had to close up and advance 'by the numbers' which slowed their progress down so I could take down Mad jack and leave the field. Casualties in the 5 bearers was high though as eventually massed rifles and baynets took their toll.
My second game was facing the dragon tong delivering a message, which had similar levels of melee troops. Keeping with a buddy proved a good tactic so you always get a hit in.
The terrain and objective type would make a big difference on how well a melee only company would work, but I could see it being effective.