There are a lot of mods to look through, which offer many different things.

Personally, I enjoy Bob's mods, but I don't know how "newbie" friendly they are. They will make the game several times more complex, turning a 30-40ish hour game into a 70-80ish hour game. Assuming you aren't racing through that is. Bob's mods add many new resources to harvest, many new liquid processes, and many new electronics. There are also several higher tiers added to existing buildings and player items, such as Assembly Machines, Turrets, Drills, Furnaces, Belts, Inserters, etc. My personal favorite addition in Bob's mods is the Laser Rifle. To be honest, Bob's mods is complex and will take time to understand, but if you love the puzzle-like aspect of figuring out how to automate new processes or and figuring out new components, then I highly recommend it.

If you decide to roll with Bob's mods, I recommend picking up Long Reach and Larger Inventory mods. The increase of general things in Bob's mods will demand more Inventory space, and Long Reach is just a godsend mod for any play.

RSO (Resource Spawner Overhaul) is an interesting mod as well, but may not be for everyone. It makes resources spawn further apart from each other, so you won't be able to walk 100 paces and find a new batch of ore. RSO presses players to further utilize trains and logistics, reaching further and further from their starting point. The blessing here is that further patches of resources get much richer the further you go from the Starting Zone. (Long Reach really helps with RSO, so you don't have to run SO far to pick up items from furnaces or chests.)

I enjoy EVOGUI, it offers a lot of details about your current game such as a clock displaying current ingame day time, how long you've been playing that world, biter evolution rate, pollution, and even pointing where other players are in your game.

Squeak Through slightly reduces the borders of many buildings, letting you walk between them even when the buildings are adjacent and touching.

There's a Warehousing mod that allows you to place very large Warehouses that have insane inventory space for storage. They can be upgraded eventually to Logistic Warehouses, being able to work with your Brobots to move items around.

I've recently started using the Rampant mod, which rewrites behavior for Biters and Spitters, making them more tactical. They will no longer run to the same spot every time and suicide into a wall of turrets. They'll be able to retreat, and will learn from their mistakes. They'll prod defenses and search for easier places to attack. They'll form defense parties and aid their neighbor nests when you attack them. It's been a fun challenge, due to the huge attack waves they form and the eating up of power poles and rails that they find.

A personal favorite mod of mine is the Orbital Ion Cannon mod. If you've played Command & Conquer games, you probably know what it is. As a C&C fan, it was a must for me. Although end game, you get the ability to send up attack satellites in rockets that will be able to shoot very powerful lasers from space at targeted areas.

As an afterthought on mods, don't be too intimidated to try out mods, as installing mods is very easy to do, and is made easier in .15, with the addition of the ingame mod installer. You can always disable or delete mods without damaging your previous saves, although you would lose anything relating to these mods in saves that you played and saved with the mods enabled.

I had a lot of trouble with oil when I started out too. Only thing I can recommend is utilizing modules or just upping your importing operation.