I don't know if you could call this a tactic or not, but I tend to do the following...
1. Equip all troopers with a decent auto-weapon, an extra clip, power armor/flying suits and an alien grenade.
2. Secure the landing zone (that sounds so dramatic), and make sure there are no aliens with launchers or stunbombs in the surrounding area.
3. Form groups of three and three; two shooters and one runner. The shooters acts as snipers, the runner as a Rambo/scout. If not fighting psykers, one shooter and two runners.
4. Kill all.
Most of my people tend to survive... I find this way of playing very useful in terror sites, especially with flying runners who throw grenades from rooftops
.
May not be the that good later on... Any advice?