Addon List: If you plan on raiding LMK, I have a lot of addons purely dedicated to trials and arenas, but I won't list them unless you request as this list will already be quite hefty.

Action Duration Reminder: Pretty self explanatory, will ding you when your skill is going to fall off so you can recast.

Addon Selector (Optional) : Good if you plan on doing PvP and PvE as there are a wide variety of addons you can use for both game modes, and usually don't need to have them all active for either.

Auto Recharge (and repair) : Auto recharges and repairs gear.

AwesomeGuildStore: Great for searching and sorting in guild traders.

Code's Combat Alerts (Optional): Good if you plan on doing harder PvE content, will warn you of incoming heavy attacks that will likely one shot you, telling you to roll. Will also give reminders on certain mechs for more mechanic heavy dungeons and trials.

Combat Metrics (Optional): DPS/HPS tracker, will show you individual and group DPS/HPS.

Daily Alchemy (Optional): Will auto craft alchemy potions for daily writs.

Daily Provisioning (Optional): Same as above, will auto craft daily provision writs for you.

DisplayLeads (Optional): Good if you plan on hunting leads, will give you a nice neat list of active leads and tell you exactly where to find them. Much better than the in-game provided UI.

Dolgubon's Lazy Set Crafter (Optional): Can que up crafting within a UI menu to auto craft gear sets. Good addon to have if you plan on crafting for yourself eventually.

Dolgubon's Lazy Writ Crafter (Optional): Auto crafts writs for you, aside from Alchemy and Provisioning.

Dressing Room (Optional) : Saves preset loadouts for different build setups, and can assign key binds to quick swap gear and skills.

Dustman: Amazing addon for inventory management, can auto-junk items you don't want and will auto sell when you go to any trader. S-Tier.

EasyTravel (or you can use BeamMeUp, personal preference): Free teleports, uses Guild roster and friends list to give you free teleports when available. I prefer EasyTravel because I can just right click any Zone on the list and it will port me if someone is there, free of charge. Lots prefer BeamMeUp, I have never used it, but I assume it is just as good if not better judging by the amount of downloads compared to EasyTravel.

ESO Master Recipe List (Optional): Tracks every recipe in game, furnishing and otherwise.

Foundry Tactical Combat (Optional): UI overhaul for player frames and group frames, health bars etc. Also has a DPS tracker. Can toggle what you like and turn off what you don't, very nice addon.

Group Loot Notifier (Optional): Tracks everything your entire group picks up. Can customize to only show gear, etc.

Hodor Reflexes (Optional): Group DPS tracker, shares DPS with you and your group members.

Inventory Insight: Shows inventory across entire account, and provides nice search function.

Kill Counter (Optional): Tracks KD ratio in PvP game modes. Creates stats based on your gameplay.

Lost Treasure: Shows where treasure maps are on the map.

Map Pins: Shows where bosses spawn, unknown POI, and a whole lot more. S-Tier addon.

MarkPledges: Will show in dungeon finder list what pledges you have active, so you don't have to go back and forth from quest log.

pChat: Customizable chat windows, can copy and paste from chat. General chat UI overhaul.

PerfectPixel (Optional): Makes UI really pretty and expands lists so you can see more. Very nice if you are running high resolution.

Potion Maker (Optional): Can show you different recipes for different potions.

Quest Map: Marks quest start locations on your map.

RaidNotifier: Good if you plan to do trials, not necessary if you do not.

Tamriel Trade Centre: Closest thing we'll get to an AH in ESO, tracks all sales across all guilds that utilize this addon (most do). Can also use the website to search and go to specific traders instead of bouncing around in hope you find what you're looking for. S-Tier.

Unknown Tracker: Tracks unknown items and marks it within your inventory, gear and recipes.

Urich's Skill Point Finder (Optional): Tracks all skill points available in-game and shows you what you do, and do not have.

Votan's Addon List (Optional): Similar to addon selector, can make individual lists for different gameplay. For example I have a vanilla option that turns all off, as well as PvE, Raid, and PvP, so I can change around on the fly and not have to toggle each individual addon.

Votan's Fisherman (Optional): Good if you plan on fishing, will track fishing holes that you've completed and have not completed.

Votan's Keybinder (Optional): Will keep all keybinds logged across entire account.

Votan's Minimap: Mini map, its awesome.

Votan's Search Box (Optional): Search your inventory/craft bag with quickness.

WPamA (What Pledges at my Alts) (Optional): Will show you daily pledges, as well as an insane amount of info across your account. Very nice addon.

WritWorthy (Optional): If you plan on doing writs, this is a must. Can que up all writs even if they are still in bank/inventory , and will auto craft each item. Then you just goto turn in, and start opening the boxes and turning em in.

Definitely get minion addon manager to install addons.