What's wrong with actually using ng-animate for ng-show as you mentioned?
<script src="lib/angulr.js"></script>
<script src="lib/angulr_animate.js"></script>
<script>
var app=angular.module('ang_app', ['ngAnimate']);
app.controller('ang_control01_main', function($scope) {
});
</script>
<style>
#myDiv {
transition: .5s;
background-color: lightblue;
height: 100px;
}
#myDiv.ng-hide {
height: 0;
}
</style>
<body ng-app="ang_app" ng-controller="ang_control01_main">
<input type="checkbox" ng-model="myCheck">
<div id="myDiv" ng-show="myCheck"></div>
</body>