I would recommend getting the "Skyrim Redone" mod. Alot of the vanilla perks are either useless or way overpowered like Agentoringe has said you can easily exploit smithing and enchantment for diabolical results. Imo, that only goes so far as you don't need super powered weapons if it only takes 2-3 hits of a Daedric sword to kill almost everything, what is the fun in that?
With Skyrim Redone, it increases the difficulty, changes up how the game works and adds a load of new things that will really give each character build a distinct feel. It also fixes/revamps/rehauls all perk trees and skills and greatly improved enemy AI. I find with the Vanilla game once you get to level 20-25 or so, even on Master with any build, everything is pretty easy especially if you utilize sneak and enchantment/smithing.
As for build recommendations, I always go with 1 melee skill (1h+shield, fast swing/moderate damage/don't take alot of damage) and either Destruction or Archery. Vanilla Destruction is horrible, especially at higher levels if you don't go balls deep into it (Basically pure mage) so I almost always go with Archery as it can easily cause more damage with the added bonus of sneak attack multiplier.
Using both 1h and 2h weapons, in my eyes, is a useless and unnecessary. "Jack of all trades, master of none." I love 2h, don't get me wrong, its much more satisfying to completely dominate someone with power attacks from a great sword or a great ax but 1h+shield is more versatile and more protective. Even Dual-wielding is better than 2h, you still cannot block but its all about damage per second rather than damage per swing, plus you can have an enchantment on 2 weapons at once rather than just one.
Heavy armor, imo, is much better than light armor in the sense that if you get the Steed stone (removes all ill-effects from wearing Heavy Armor) it practically is the same thing but protects a vast amount more. With that you should always invest a little bit in Enchantment and Smithing (I know I went on a rant about it being overpowered, but still XD) to create weapons/armors like no other. (In that case you should also invest in Alchemy to increase enchanting/smithing potential)
Lockpick/Speechcraft/Pickpocket are all, 100 percent, completely useless and the only reason you would invest perks in either of these is to get the one that increases your carrying capacity, but even that is pretty obsolete.
For magic schools, Destruction is vital if you don't go with Archery. Illusion in vanilla is pretty bad, its only good till around level 15 and becomes pretty useless and is only there for the novelty of it. Its a shame really, I really love the concept of turning your enemies against eachother and it is very fun in the beginning. Alteration is a good skill to have with the improve armor rating spells and magical resistance but even that tree needs alot of work to be worth all the investment. Conjuration is a fun skill, but don't overextend yourself into all the magic schools, it takes alot of perks to master any one of them.
Sneak is a horrendously overpowered skill and almost every enemy including bosses become child's play when you master it and take full advantage of sneak multipliers. Its probably the easiest skill to master as well if you're like me and sneak attack every chance you get.
Like I said, I strongly recommend "Skyrim Redone", it removes all the overpowered skills, balancing things out and makes the game alot harder but much more enjoyable to play. In the end, its all up to you, Skyrim plays alot different than Oblivion ever did in the sense that as long as you don't invest too many perks you can switch up your style willy-nilly. Any build at later levels (20+) is going to be a killer no matter how you go, unless of course your build is like Dr.Phil there XD. Good luck, I've probably created around 50 characters so far because I just can't get it right or I lose interest in them.
I finished the whole main quest with just a sword in one hand and a shield in the other!
