Agree. A PC with the opportunity for a good HP total, a good rate of resting HP recovery, (both due to a d10 HD), proficiency in good weapons and good armour, and (at higher levels) the extra attack feature, pretty much has everything that makes her an effective fighter in 5e.
The archetype features really just add opportunities to be slightly more effective in some circumstances, or to be equally effective but in a slightly different way. Battlemaster and Champion do offer different opportunities to modulate effectiveness. However, in-play I think that the main difference between the two archetypes is really just that the Battlemaster requires a bit more player thought to take advantage of these opportunities.
The Battlemaster can be really effective in-play if the correct circumstances do arise, and the player recognises this and responds appropriately. Equally the Battlemaster sometimes offers very little over a "no-archetype" fighter. For example, if the player has frittered away all the superiority dice in a flurry of needless but fancy footwork in a previous encounter. Or if the player is "saving" superiority dice for the next encounter.