Using the basic gallery is quite easy, but like you say, if you want to take advantage of the flexibility in creating custom pages, you need to dig in a little.
The textpage will allow you to display custom text, some logo and perhaps a small photo. The filemod/photoblinds only allows you to display a photo with a basic description above.
As for custom fonts, do you mean use an actual CUSTOM font? You can of course put any text you want there, but you can just use ANY font. Just like HTML, you are restricted to font families, or groups of fonts that are available on most computers.
Unfortunately, there is no wysiwig editor currently, but we are trying to add that to 2.1 release. If you want to change the STYLES/FONTS of the text, you may need to edit the CSS file. This is not easy if you never worked with CSS before, but simply changing a few values should not be too difficult. Read more on CSS:
viewtopic.php?t=4270
You "can" integrate a few thumbnails, but I am not sure I would recommend it. Flash textfields(as in imagevue textpages) are not completely identical to standard html pages, and it is a bit tedious getting images to display as you want them, and of course, it is a manual job for you to add the thumbnails. However, fi you do, it would not be a problem to link them to separate galleries, but it will be a manual task for you to create and manage.
Generally speaking, I would recommend this: If you want to display a generous amount of text and some logo, you should go with a textpage, and perhaps try to keep it simple. If you only have a little text, then you could use the photoblinds startimage and display your text above the picture. You could for example create a startimage that includes your logo transposed over one of your designs/photos...