I’ve been only able to complete the game with the hunter, but I’ve just recently managed the same w/ cleric in IMO way too few tries (like 3-4? I may have been lucky). What I like about him:

• you get the “guiding light” from begining. It does some damage and guarantees first hit, you can upgrade it - that is enough for most enemies at least first 5 levels used sensibly.
• you also get the “holy intuition” ability to determine if an item is safe to use - for little cost. This allows me to be much less conservative when using new weapons / armor since I usually don’t get to learn how the scroll of remove curse looks like before level 5. That is so much of a gamechanger for me, I’m almost afraid the ability is going to get “nerfed” - at least get costlier .
• around level 5 you get to the “sunray” or something - cheap and practical - lasts like 6 turns -I use it all the time, does some damage and the enemy really doesn’t see you until you are one block away. great for ranged enemies. You can blast somebody w/ it and just run away.
• and finally you get “some spear” - I don’t really reacall the name - that allows you to “raiders of the lost arch” style one shot pretty much anyone you don’t really want to bother with. Quite usefull above level 20. That one is slighlty costlier though.
• and than are the honorable mentions like the ability to walk through fields of traps “devine sense” , and “recall inspiration” that sounds interesting but I’ve never managed to use it…

Edit: sorry - got carried away - in case of tengu I suspect I’ve been lucky enough having strong armour (i’ve identified all of them thx to the intuition feature an wearing it / some scrolls of identify - i don’t use spells of upgrade until i get to the metal armour - if i can help it) and as usually I’ve brought every ranged / throwing weapon i’ve managed to pick up along the way and had the book charged up and had some potions of health for fighting while being aflame…