So many questions, and so many answers!! Most of your questions fall into the user opinion. For example, Evo vs OS engine. In the 46 range, the Evo comes broken in, and is close to optimum settings out of the box. The OS engines are reliable, but there is a big difference in power between the cheaper LA series and the more expensive AX engines, primarily because of the bearings. Personnally, I recommend the Thunder Tiger Pro 46. It has the power of the AX for the price of the LA.

A fuel pump is not necessary, but it is convenient. A 4 oz bulb works good, but you'll get fuel on your hands. Set it up such that you're pumping fuel into the tank through the fuel feed line to the carb. Disconnect the line from the carb to prevent flooding the engine.

As for starters, I have an electric starter, but I mostly use it for winter flying, when the engines are very hard to start. I normally use a chicken stick, and with the exception of the first start for the day, my engines start on the first or second flip - The first start may take a few more. If you get the Avistar, you may want to start off using the chicken stick to prevent messing up your cone. Flipping backwards tends to work better. A couple times not holding the starter tight enough agains the cone and you'll have a permanent ring gouged in the plastic. Also with the chicken stick, I've never had my starter battery die.

Tuning is a little different. You'll want to find the peak RPM while adjusting the high speed needle, then turn it back to the rich side a few clicks (300-500 rpm). You want the airplane engine running rich on the ground so that when it leans out in the air, its not running too lean. You may need to mess with the low speed mixture a little, but wait until the engine is fully broken in. Your engine manual should describe how to do it.

Before you fly your newly built plane, whichever one you decide on, take it to your local club and have them do a thorough pre-flight inspection. There are many things they'll know that aren't included in the instructions. Even if its RTF, there a few things to do to make sure it ready, such as keepers on all servo arms, making sure control surfaces don't have too much play, verifying center of gravity, etc.

Glad to hear you've got an instructor. If you're a quick learner great! You'll save yourself a lot of frustration and $$$. A few weeks on a buddy box is well worth a lifetime of enjoyment. Most decent clubs offer free lessons to members.

Best of luck!
Brad