i like the ideas. But i wish that there was a more structured gameplay. I often don't know when its my turn or what turns i have available. Maybe it just needs a few sfx to indicate or a risk-style three-step gameplay that is signalled somehow on screen.
The thing that i don't like is the lack of clarity on some points. Like begins and ends in the same colour implies two spots minimum. And its often unclear what an empty string should do.
there is one problem... the birds look different and can look similar to bonuses... and with the busy background speeding past i can't tell the difference until its too late.
resource buildings with the bonus should have a glow so you know not to collect there. And they should have a bar that shows how full they are. without mouseover.
the units should specify 'turrets' 'defenses' and 'resources', not 'defenses' 'walls' and 'resources'. The wording is inconsistent. Also, i feel kamakazi should be able to target all 'defenses' (by that i mean all structures under the defenses tab in the shop.
the game seems a little easy. But the main detraction is there are too many TD games with the same concept and this adds nothing... kingdom rush instantly comes to mind... its almost like a copy with different tower upgrade system. sorry 3/5