I bought the unflavoured Huel as I also would not want sweet food all the time and want a variety of flavours and so far have tried the following:
Bananas and cinnamon (the best one yet)
Bananas and cocoa powder
Avocado (one in 100g Huel, could hardly taste it, will try two next time)
Raw spinach (bright green, but no flavour)
Bag of mixed salad leaves and a splash of balsamic vinegar (enough to override the oaty taste, but still weak)
The ingredients in the Knorr pots is not great, 90% of it is made up from water, glucose syrup, salt, vinegar, palm oil and sugar. Some fresh herbs might work. I will give that a go.
I plan to try other green leaves like kale, other fruits and also Marmite and coffee now (thanks Julian and Geby).