Yup, by using the "Append Text" node, you can collect everything into a long string from different sources, and then use the "Split Text" node to separate it into a list of texts based on a separating character (":" for instance). That character may be added in the XML, or by using the "Append Text" node for other sources. "Split Text" might also be able to "ignore empty" iirc, cutting out the empties if there are any. I.e. if using : as separator, a :: text list entry will not be made I think, but a : : will as it contains a space which is a character in itself (looks empty but isn't technically).
To clarify the formatting a bit; when making a text layer it will apply the style formatting to the text and create an image (in a broad sense). Making a text (as in "Append Text) is only a string, so that won't have style info attached. So in the composition I attached previously you process a list of text (strings) into a list of layers (images). If you process a list of text by attaching or adding something to the text instead, you'd end up with a list of strings that wouldn't have any style info attached. That can again be processed into a list of layers though.
Use the Process List node to collect the text into a list. As a bonus, you'll get a tidier approach to the whole comp as well :)
This will depend on how you generate your text to begin with though as any open spaces in the list still will generate a split. I've included one possible option in the comp, but this will have to be adapted to your use case.
I think the reason for it duplicating the last item in the list is that it makes it easier to deal with point-lists and transforms for instance. With it "remembering" the last instance for the rest you can quickly make a translate array providing only the transforms and adjust rotation and/or scale in one line instead of making separate lists containing the same value. Definable behaviour on the out-port would probably be nice though.
A workaround for the slider range is to publish the port and then right click on it and edit details (also sets default increment size). Also for easier placement, add a layer under the images you want to place and then use that as a guide to place them on the canvas. An additional way to attack it is to snap guides to the center of a selected layer in AI(? I just use Phototshop, but I'd guess you get the same info in AI?) then observe and note down where the center point of the layer is. Then it should just be a matter of typing in the coordinates.
I think this has been discussed before, have no idea where - probably in the km that contains the beginnings of the Vuo 2.0 redesign.
The reason for the colors being what they are is that they are compatible with the Brewer color scheme for color blindness iirc. I think one of the options that came out from the discussion was that there could be a possibility to create your own color scheme and so on - but it might be me misremembering as well. Composition notes will solve a lot of the organising challenges though.