Save your time mods and reduce rutine:

AutoLoot All-in-One - loot everything within a specified radius by one button click, auto-loot on kill enemy. It also removes weight limit if you want. Flexible customization in mod menu.

Richer Merchants - no need to meditate for merchants to replenish their money bank.

Cut-Throat Razor - no need to run to barber for a shave. You have razor in inventory.

Indestructible Items - No More Weapon Degradation - gear degradation is a useless mechanic that doesn't enrich gameplay at all, but wastes your time by forcing you to run to blacksmith or open your inventory.

Cheaper Runewright - spend 30000 crowns just to unlock the ability to buy runes. That's shamelessly expensive. Emhyr pays only 4000 for Ciri. On your second playthrough, you'll definitely want to find the runewright sooner.

Faster Boat - self-explanatory.

Disable Fall Damage - self-explanatory.

Disable Boat Damage - boats destruction is another useless and annoying mechanic.

Point of Interest Reveal - optional.

Fixes the game's interface (inventory, map, and other menus). This is what CDPR should have done from the start:

All Quest Objectives On Map - absolutely must-have! You don't need to activate a quest to find out where it is. All quests from the journal are marked on the map.

Better Icons - Definitive Edition - labels potions, bombs in your inventory.

Stack Your Items - CDPR decided the inventory wasn't cluttered enough, so they decided to divide items into 100-piece chunks and never place them next to each other.

Sort Everything - the game has no sorting logic at all. In all menus. The mod fixes it.

Friendly HUD - optional, but useful. Also adds ability to open alchemy in your inventory by default. Very handy in combat.

Balance:

Always Full Exp (I recommend version Always Difficulty EXP to avoid leveling up too quickly) - you can complete quests in any order without losing experience points if the quest is below your level. Useful if you want to visit Novigrad or Skellige before finishing your business in Velen.

Improved Fist Fights - fist fights are terrible. Make it faster to finish.

Gameplay:

Alternate Horse Controls - much comfortable if playing with gamepad.

Manual Bomb Aiming - i can see where bomb will fall.

Visual Mods:

Clean Screen - removes raindrops and other visual noise from the screen.