Altus is one step up from entry level, but it isn't bad. Shimano uses a trickle down approach to their component groups. Today's Altus was Acera 5 years ago, Alivio 10 years ago. STX/ Deore 15 years ago.

Is the 7.4 a better bicycle? Sure. It is lighter on account of the CF fork and has better components that should run smoother and last longer. However, the Altus components will likely last a long time as well when used normally (not abused). Does it matter to you? Test ride both bikes and decide for yourself. Either bike will get you where you want to go.

Keep in mind it is a lot cheaper to buy a bicycle with better components now than it is to try to upgrade later. So if you think you like the 7.4 better, get it now rather than thinking you can turn a 7.2 into a 7.4 later.