Note that you can manufacture and sell off laser rifles fairly handily, generating income during periods when you don’t have other things to do with your production capacity, and without using any resources like Elerium. Also, laser research can be started before you get your hands on alien tech.
I liked to set up between 4-6 rocket bikes with the best available cannons and use them to do shootdowns. Sure they can be taken out by the aliens, but heavier ships also get wrecked or destroyed regularly, and cost a lot more. I sometimes coordinated a heavier ship with “fighter swarm” of rocket bikes. I do NOT like to send a transport full of troops to do shootdowns; getting a squad shot down is a great way to suffer a crushing setback.
One thing about training your guys – they improve accuracy by taking lots of shots. Give some guys submachine guns and use the “terrible accuracy, low time unit” shots to spray fire all over the place. You’ll miss a ton and use up a lot of ammo…but your guys will get better quickly. Then rotate those guys to laser or plasma weapons and rotate your other guys into submachine guns to train them.
I always liked to bring along one or two rocket launcher guys even late in the game. It’s a freakin’ rocket launcher! Guys near them can hump a spare rocket in their packs and drop it if you need to reload. Make sure your rocket launcher guy is pretty accurate, and DO NOT LEAVE HIM WITH SPARE TIME UNITS or otherwise set him up for opportunity shots, as he will happily fire into a crowd of your guys and kill buckets of humans. Instead, use him for planned artillery fire missions (rockets do big area damage!), destroying obscuring terrain like bushes, and, in emergencies, killing downed aliens who might revive and put the hurt on you (they are just wiped off the map like equipment by the blast radius). That’s expensive, but if your squad is in trouble, winning a costly battle is better than a teamwipe.
Tactically, I HATE running out of time units as I scout forward; eventually that led to my developing a preference for setting up crouched ambushes and “fast forwarding” until the aliens came into view and (hopefully) fell to opportunity fire. That can get dull, and some folks don’t have the temperament for it, but an arc of prepared guys all facing a door with saved time units (some of them on accurate setting and some on spray fire, although I’m not clear that affects their AI for opportunity fire) can give a VERY hot reception to aliens who pop out to throw something at you. If they hole up and don’t come out, you can always change tactics and start advancing using a bounding overwatch. I fought most of my battles from set-up defensive positions whenever possible, to minimize losses.
I paired this strategy with proximity mines (the human ones and, when available, the “hopping” alien ones). Prox mines are great! But do set your guys well back from them; a morale break can lead to your men running over their own proximity mines, which although tragic, is hilarious. If you subsequently need to advance over your own prox mines, they can be safely erased with grenades or rocket launchers like other equipment.
And nothing beats hitting “next turn” while set up in defensive positions with prox mines in chokepoints, and watching an alien turn consisting of “BOOM BOOM BOOM”…victory screen!
It may have been more for fun than for effect, but I always liked giving one or two high-time-unit guys the energy sword, which used no ammo, and using it mostly to bayonet unconscious aliens to death (once I’d researched their type). There’s something vicious but satisfying about bayoneting the fallen!