Little strategy help?

So I've been playing GC for a long time, on and off, here and there. I like my basic strategy of all-banks on the first world, all labs for two years on other worlds, then switch to all-factories and churn out the war machine. I disable tech trading, and go slow if need be in the first year to develop population and economy. My all-lab/factory worlds usually add a farm if there's room, for more people, and I use breeding abilities to speed up the taxables. I typically research some dip, then some research, then more dip, weaps/miniaturization/hulls, then I research up good factories before I switch. This all works decently well for me, and by focusing my abilities and gov't primarily on econ, I avoid the pain of staying on the razor's edge of -500, which I just don't find enjoyable.  I also last out two years as opposed to one or 1.5 for the research because I'm really a tech fanatic when it comes to 4X games.  I only war because I have to!

But I have a few holes in my overall strategy: I regularly lose out on the second wave of colonization. I still don't know whether to buy my first colony ship, and I stress out about exploring the galaxy around me; it feels like I'm still way too slow on the first colony rush, but it's usually that second wave (grabbing the small leftover planets) where I lose out. On a larger galaxy, I definitely colonize fewer planets in the first rush, too. What are the best colonization strategies?

Secondly, I feel blind regarding the one-turn war. I do okay with it -- here's what I do. I develop fleets of 24-logistics points: two large ships with HEAVY weaponry (and low defense, because I hate trying to match it up), and two cargo-hull transports with two advanced troop carriers each. Speed winds up around 7-10. Then I take two of these fleets to park by each major planet they have. They declare, and I attack. Again, it's the little-planet cleanup that I hate, but I almost always eat their capital planets right up. Is that about right? Is there a better fleeting strategy? I really don't know anything about the "proven" fleet strategies for this tactic; this is just my blind guess. 

For later wars, I keep the non-transport ships and upgrade them as necessary, always watching my money to make sure I can!  The HP bonus is entirely worth it.  This also confuses me, though: why do I go with SO MANY factories, when I start WAY out-producing what I can upkeep, and WAY WAY outproducing what it takes to win a war?  In a few turns, I have a war machine capable of a one-turn takedown.  In the future, I think I may start trying an every-other-planet all-banks strategy; unlike labs vs. factories, it won't waste any slider space.  With enough breeding, the maintenance is negligible.

Any other advice would, of course, be handy. I'm just playing challenging games so far, but I'd like to move up the ladder. I'm doing just fine, but I want to solidify my methods first!