Lego Marvel Avengers

[Golgo]

Correct me if I am wrong but doesn't Skylanders go by the following design:-

See an unreachable area, got to buy a character to reach it.
or
See a blocked path, you need to buy a character with big smash fists.

To some degree, yes. However the extra areas behind the blocked paths, etc., are always minor and have no bearing on the campaign or awesome plotlines. The main draw for buying extra characters - of which I (ahem / my son now has 21 across 2 games) - is just to play as them and unlock their abilities/skillsets, which are always really imaginative, well animated and fun. You can then use them in PvP, horde modes and other challenge modes, of which there are a lot. Anyway there's a ton of content in there (we've got Swap-Force and Trap-Team) without ever buying anything else but the starter packs.