Along with Friendly HUD, I used
HUD Positioning And Scale. Really let me customize the game's HUD to my liking.
Live Bestiary is a nice touch if you want the monster journal to feel more interactive/alive.
I enjoy going where I want. I do not enjoy being penalized for sprinting at night and failing to see where I'm going.
No Fall Damage allows the player to survive a drop from any height. This is a relief to people like me that like running without looking; there are no consequences if Geralt wanders off a cliff - which happened to me far more often than it should.
If you ever get tired of the same music selections,
Familiar Music Replacement lets the player pick different music
(from tracks chosen by the mod author).
Here's a controversial one, but I really enjoyed
Leveling Witcher and Relic gear BALANCED. It automatically levels up all your Witcher gear and your relics with you as you level up yourself.
(It does not level up standard equipment.) I would more recommend this more for a second
(or third) play-through, but if the idea of constantly searching for new loot frustrates you - and you just want to stick to the story - you might be interested in this. This can break the economy a bit, as the player can just hoard older relics and sell them later.
(Higher level equipment = higher value) But I found myself having no desire to grind end-game just to afford the niceties that the DLC offers in-game, and suddenly those highly-leveled relics came in handy. ...Worth noting that even with the mod installed, it is still worthwhile to complete Witcher gear scavenger quests if you intend on visiting the merchant adding in the first DLC to formally have 'Superior' Witcher gear.
(The chest piece needs three enchantment slots.)
Script Merger is great. Make sure all mods are v1.31 compliant. If you are using a mod that is old but reasonably popular, the community might very well have made an update patch for it to make the mod v1.31 compliant. There is a list somewhere (Script Manager page, perhaps?) which shows which mods had community-made patches.
* research if a mod is v1.31 compliant
* if not, see if the community made a patch to make the mod v1.31 compliant
* install the mod - and all Witcher 3 mods - with Witcher 3 mod manager
* use Script Merger to merge mods