It can be as simple as that. For the amp-hours I would not go below 20 x standby current. I also would select at least 5 x current at peak power (the one you want to actually use - not necessarily that of the rig). Less will result in voltage drops during transmission. For portable use I go lower but the voltage drops significantly during transmission. In portable use weight is an issue, for base stations it usually is not.
I also use two or three gel batteries. That way I have one in use, one on standby and one recharging (e. g. on a solar panel).
My base station is a Yaesu FT-7800 running on a 7.2 Ah lead gel battery.
I second going for the power poles. I liked them instantly. No male or female connectors and still right polarity can be encoded in a pair.

73 - Max