Classes mostly determine starting stats and skills, and you can re-roll to go for different starting values. The biggest issue you'll have will be carrying capacity. You're not going to be able to use Plate effectively, and hopefully you didn't plan to use axes as your weapon of choice (axes are probably the heaviest of the weapons). There is plenty of good leather and chain available, so this isn't a big problem.

Find a room or two on each level to store things so you can find them again later. You can make notes on your map to help you keep track of what you've put where.

The big thing the shepherd class does in UU is allow you the widest range of skill customization. Most other classes have a bunch of preset choices, but shepherds can choose more or less anything.

Here is a playthrough of UW1 with a str 17 mage using only leather armor:
https://www.youtube.com/playlist?list=PLz5vvzhI-sz7HdQlCY7NunVmgOrewzCV2

It's doable, but if you play the game the first time I would advise having a higher str, because it makes the game much easier. And if this is your first playthrough, you don't really know which items are important and which are not, so you will be carrying more unnecessary stuff around.

Thank you all for the answers!
I have the sword skill, thought it would fit the bard the most. Never thought that i would be able to wear plate armor with my bard, so i am not that disapointed.
I am going to make some storage rooms and mark them, thx for the tip! BTW the automap and notification feature is really awesome for a game from 1992.

You might not want to deposit too many items on one floor, as UW1 has some kind of inventory bug, that will get you an overflow, if there are too many items on one floor. That might result in items changing or disappearing and you losing mission critical stuff. If you make storage rooms, make several over several floors and distribute your stuff.

Just leave the floor 1 stuff in the floor 1 store room, floor 2 stuff in floor 2 store room, etc, and you won't have to worry about the bug.

The two of them ended up with their stat allocations reversed in UW1. Lore-wise the paladin should be the one with high Str/Int and the druid the one with high Dex/Int. UW2 fixed the paladin's stats though, so it's a good choice there.

Yes, but lore-wise (and throughout the relevant games of the main series) the Paladin is the class based on Honor (Truth/Courage), with high Intelligence and Strength. The Druid is the class based on Justice (Truth/Love), with high Intelligence and Dexterity.

UW1 apparently got that backwards; UW2 brought things closer to the setting standard.