A rough "rule of thumb"
17Lb (all up weight)
150 Watt per LB (Aerobatic but not 3D)
~ 2500-2600Watt motor.
This falls just within use of a 6S LiPo, which I would at least explore, due to the cost and availability of motors and SECs that are rated for higher voltages.
From strictly a current stand point, an 8 to 10S battery might be more preferable if the other variables work out.
Is an example of a motor that might work if the higher voltages are used. (two 5 or 6S LiPos in series)
If an external BEC is used, remember to tap the battery that has the negative lead in common with the SEC negative lead.
Many of the external BECs are rated at up to 6S input only.
Working backwards, the maximum prop size may dictate that you adjust the desired KV motor range and voltage.
9 to 12,000 RPM is usually a desired range for electric motors, due to such things as Prop RPM max ratings.