Jim,
Being a beginner myself I'm not sure I can offer much in the way of help with your question. I do have a few hundred hours in full scale planes though and maybe this will help. All planes will tend to climb from level flight when the throttle is increased. Increased throttle increases airspeed which increases lift and up you go unless you put in a bit of down elevator. What I do on my models is set all control surfaces even with whatever they are attached to, wings, stabilizer, or rudder. Then I take off and use the sticks to keep things from misbehaving until I get to a safe altitude. Then I center the sticks and click in trim adjustments until the plane maintains straight and level on its own. The throttle will still make the plane want to go up or down depending on how much power you apply but that's just something you anticipate and deal with manually.

John