Why? Because the Mechromancer class just has so many great skills that you have to neglect points in a couple of spots in order to reach others. Gaige just has so much flexibility after all.
This build can easily be modified depending on your personal preference. And remember that using class mods can help you fill in the gaps left behind in some areas.
I'd like to mention that this build still provides high damage per second (DPS). It doesn't have all the elemental damage perks from the Little Big Trouble skill tree. Additionally, this build still gives power ups to your sidekick Deathtrap so that you two can duo well. Since this is an Anarchy build, a lot of points were put into the "CLOSE ENOUGH" skill to help counter the reduced accuracy. This will help you take potshots and actually hit enemies still, as well as make it easier to come back from FIGHT FOR YOUR LIFE -- so you don't have to worry as much about dying now. To further enforce the great solo abilities of Gaige the Mechromancer, 1 point was put into BLOOD SOAKED SHIELDS so that you can utilize your shields for more protection.
Best Mechromancer Skill Build
*** Summon Deathtrap ***
*Best Friends Forever*
Close Enough (4/5) - Bullets ricochet chance: +40%, Richocheted Bullet Damage: 50%
Cooking Up Trouble (3/5) - Regen health while magazine is full: 1.2% of max health per second
The Better Half (5/5) - 60% increase in fire rate when magazine half empty
Potent as a Pony (5/5) - Increase maximum health for you (20%) & Deathtrap (10%)
Upshot Robot (1/1) - Increases Deathtrap duration (+5 seconds) & melee damage (4%) per kill. Stackable.
Unstoppable Force (2/5) - Bonus movement speed & shield regen after killing enemy: Movement Speed (14%), Shield Regen (1.6%/sec of capacity)
Explosive Clap (1/1) - Deathtrap causes explosion in front of him for Explosive Damage.
Smaller, Lighter, Faster (4/4) - Increases Reload Speed (24%); Decreases Magazine Size (-4%)
Anarchy (1/1) - Killing enemy / emptying magazine in combat gives you stack of Anarchy for increased damage (1.75% per stack) and decreased accuracy (-1.75% per stack). Anarchy Stack Cap: 150. These are lost fast during FIGHT FOR YOUR LIFE.
Preshrunk Cyberpunk (5/5) - Increases max number of anarchy stacks (+250)
Robot Rampage (1/1) - Deathtrap lashes out with a flurry of attacks.
Blood Soaked Shields (1/5) - Immediately recovers portion of shield (20%) after killing enemy. Lose 1% health.
Annoyed Android (1/5) - Increases movement speed of Deathtrap (7%)
Discord (1/1) - Prematurely reloading grants you bonus Accuracy (65%), Fire Rate (25%), & Health Regeneration (3% of max/sec). You lose anarchy while activated. Reload again to turn off Discord.
Typecast Iconoclast (4/5) - Change to gain additional Anarchy stack (24%)
Rational Anarchist (1/1) - Gain 25 anarchy stocks instead of 1 when at 0 stocks.
Death from Above (1/5) - Digi-splosion when killing enemy while in midair (consume 1 Anarchy stock)
The Nth Degree (4/5) - Every 6th bullet that hits an enemy will reflect toward another nearby enemy.
When additional DLC / downloadable content is released, then even more skill points will be at your disposal so you can fill in the gaps where needed and even finish skilltrees if desired.
But until then, you must spread it out a bit more.
And there you have it! Have questions or know of a better solo build? Then please comment below.