Bandai is your only choice as far as company. For models, the HGUC RX-78-2 Revive ($10-$12 USD) or the HGAC Leo ($10-$12) are fantastic kits and great for beginners due to their simplified construction compared to their counterparts. The rest of the HGUC Revive sub-line also are very good starter kits (I myself started with the HGUC Gouf Revive).
They've more solid articulation all around than most Bionicle figures IMO. More recent HG kits (from ~2013 onwards) make really good use of double-jointed knees and elbows, and superior shoulder- and hip-joints to Lego constraction figures.
By the way, do you already have the necessary tools for assembling model kits?