Buildings may actually be hacked down fairly easily. A pierce armor decrease could be explored tho.

I agree that attack by default is more familiar to the RTS player. maybe we also will get more widespread feedback from the RC and can make a change based on that. Perhaps a setting could be the ultimate solution.

@Vantha Do we have a tip for that? (Can't find the tips in the repository.)

Ideally soldiers except siege ignore buildings and only attack enemy units. When force attack buildings, capture is most likely easier because the 0ad buildings have way too much health compared to units and damage done by units. But if it's ungarrisoned, then a capture is quite easy. Ultimately, it should be up to the player so we can keep it like status quo. In any case, you can edit your unit_actions.js to change the behaviour of solder units and their hotkey associations. My recommendation is to decrease the pierce and hack armours of buildings because they are too ridiculous high at the moment.  

Finally defeated 1v7 very hard AI on mainland in 3rd try xd. So, all it take is to stop Ais trading and keep annoying them in middle and you would have chance. the passive attack never works. 

Nah that's another issue Those files probably either don't exist or are in another folder.