I would go Haggling 1/5, Allure and Merchant. When you reach higher level, Investor may be useful.
Let me explain: when after leveling your alchemy you have a tons of potion in hand, and after leveling your Smithing/enchanting you will have 400 Dwarven Bows enchanted in stock, you will want the Merchant perk.
If you don't have the Merchant perk, Potions can only be sold to alchemist and general store. Dwarven bows only to blacksmith, fletcher and general store, and they don't have enough money to buy more than 2 or 3 at a time. With Merchant perk, ANY vendor can buy those items from you, that will make your life easier.
At higher level, I would take Investor and invest ONLY in the general store in Riverwood. For me it is the only merchant that worth it, but damn he's worth it. The reason is that at higher level, chances are that you don't need to buy anything anymore but you will find loot that are increasingly valuable, a lot of them OVER 1000 or 1500 gold. Those loots, majority of vendor won't be able to buy them from you EXCEPT if you buy other item from them first. And there comes the Riverwood General Store and its 11K gold every 48h. That way you don't have to fill your house with useless loot anymore.
Fence, for me is not necessary. I LOVE to pickpocket and steal (I'm a thieve, after all) but by doing the Thieves Guild questlines and side quests, you will have access to at least 6 fences all over Skyrim. Enough to get rid of your stolen stuff, so no need to spend points in that.
Master trader is a little better than Investor overall, but as you already have your Riverwood Trader at 11K, then it is not really needed anymore.