Below, you can download the widgets I've made (.kwgt files that can be used by KWGT directly) and adapt them to your needs.
The time is writ large, the date is easily legible, and both are rendered in a clear, friendly font. I found it difficult to find a ready-made clock widget that answers precisely to this description, though the main reason I made this widget is that I can duplicate it and view multiple clocks in different timezones simultaneously.
The timezone can be changed by adding a location in KWGT's settings and then applying it to the widget in the editing screen (under "Layers"). At the moment, only three locations can be set apart from the home location, which I hope will be resolved in the future.
This widget displays the number of megabytes used since a set day in the month and shows a bar progressively filling itself up as one approaches one's limit.
It uses three shapes, described below.
Rectangle: $mu(min((ts(mt, m, 3d)/250)*474), 474)$3d refers to the most recent 3rd day of the month; my contract runs from the third of each month. Change this to whatever date your contract describes.
Text: $ts(mt, a, 3d)$
474 refers to the final width of the bar; you can change this to whatever value suits you.
250 refers to the monthly MB limit, 250MB in my case.
Indicates current weather. There's a refresh button, and tapping the big weather icon opens a weather app (set to Forecastie, you'll likely want to change this). You can set refresh rates in Kustom's settings, but I also like to refresh manually when I'm about to go out.
Indicates current weather. This widget is a modified version of the previous weather widget, adapted to my current layout. It takes up less space, but displays the same information. Tapping the weather icon opens a weather app (still Forecastie), tapping the text refreshes the widget.
As KWGT's default weather descriptions are so long that it's difficult to incorporate them into such a compact widget, this widget uses shortened, simplified weather descriptions.
I prefer RSS feeds to websites, and I use a dedicated RSS application for most of my information intake - it, however, has no widget, so this widget wgets an RSS feed of your choice and shows the title of one item. There's buttons to page through the items in the feed, and tapping the title opens the article in your browser.