Hi Richard,
Thanks for replying!
1. Too bad I need to edit the plugin code directly, that's not update-friendly... May I suggest that the text is made user editable in an upcoming version of the plugin? Fortunately, my site is completely in English; not Dutch translations to worry about.
2. As for my wishes on the CSS-part: I'd love if the look 'n' feel is more like the search box:
2.1 no 'subscribe' (or 'go', in my case) text but instead a small button inside the text input field (comparable with the little magnifying glass in the search box example).
2.2 The font style should be identical to the default content font style (which the search box complies to). The Widget title does comply with the other widget title styles, but the text inside the input box does not.
2.3 Minimize spacing below the input box