Re: Strikers
The most generic ratio given for striker route is something like 4 marine, 2 striker, 1 apache 1 gren. I don't like this though, it's trying to cover all possible situations, and so it ends up not really excelling in any.
If you're in a reasonable alliance, then your main use will really be armour killing, so in that situation I make myself as good at this as possible, something along the lines of 10 striker, 7 marine, 1 apache. In alliance battles, apaches generally fire too late to make a big difference, and TDs do the same role alot better. You'd do better to get an ally with SAs/Vamps to do the health damage rather than waiting for the apaches.
As a solo you'll have more trouble with flak attacks, so you'll want more apaches. Apaches are also *really* scary to see in large numbers when hacking someone. A large RPG might even think twice about attacking you if he can't be sure that all those apaches will be gone (taking into account he can't be sure how many marines you have), cos Apaches will take a stupid amount of punishment. So something more like 1 striker, 1 marine, 3 apache 1 gren if solo or in a poo alliance. With that you can power your way through any health route, and some poor armour setups, taking flak losses, but still raping.
If no marines... I wouldn't play that route unless supported by a good alliance. HWs are reasonable flak, but its just irriating being eta 6. And grens, although they have quite nice damage, they do drop like flies. Privates would work very well as flak I think in individual battles, but I doubt it would be cost effective in the long run.
But those are only my suggestions, using my past experiences with strikers which depended alot on my situation at the time. There is no one set ratio that will be perfect for everyone.