About the spawntimer. I too think it's too low, but not much. From what i have seen there are mainly some spawnpoint problems for certain flags. I've seen all castles get captured and the fact that those maps were played for the full 2:3 or 3:2 kinda indicates that the balance isn't that bad (Not saying it's good, because it's not). You guys seem to forget that defense doesn't spawn at all once you got the flag set to neutral. As short as the timer may seem, holding the flag for a few seconds so noone spawns there anymore balances this out. Not to mention there are different approaches you can balance those maps.
For example, i made helms deep with the 20 seconds def spawn timer in mind so i set the spawnpoints of the flags where i think the average way for attackers to reach one flag from another is about or a little above those 20 seconds. Meaning def spawns are close to the flags themselves. But teeth, who made Isle of Cray (The one where the barracks are completely broken if not taken first^^), let defense spawn without penalty, meaning they spawn after 3 seconds, but set the spawns so that the time for both teams to reach the flags is about the same. Makes for a little more walking but less waiting time for def to spawn, but in the end from what i've seen it kind of was balanced.
I think teeths approach is the best because everyone gets to play almost 100% of the time, but it makes for a WHOLE different set of balance when it comes to spawnpoints.
Basically what i'm trying to say here, is, that battle maps are easy concerning balance, siege maps are hard and conquest maps are a pain in the ass to balance out. So it comes down to testing it live on the server. Hate me all you want for pulling you through this horrendous struggle of x1 for 30 minutes or more, but concering the 4 conquest maps that were played, that's a good thing, simply because they will be a lot better once they come back.