Hi Rafa,
I'm not a plugin developer so I can't comment on the best workflow. I can
say that I'd try use a more lightweight host than Ardour. Have you tried
running your plugin using the example jack host that comes with the
LV2-core source?
<shameless self-promotion>
In case your intrested: I've written a simple C++ host class, in case you
want to write a host specifically for testing purposes:
https://github.com/harryhaaren/Lv2Host
</self-promotion>
Are you documenting what your doing in a blog or so?
I'm hoping to get writing LV2 plugins, but I've never found a "newbie"
style tutorial..
Cheers, -Harry