Dug, I have hike the Meysan Lake Trail a few times and it is: 1) longer, about 5 miles to the lake about a mile less to the pond (treeline)2) the trail is steeper 3) elevation gain is significant 4) depending on date, a little hotter (I always start around 5:30am to avoid the sun and heat.
Having said that, take it slow and easy. If Meysan Lake is your destination, I think the views are spectacular. The kids will really feel they've accomplished something.
Paul