Many people are surprised to discover there are designated ministries for lay people. On a practical level, this doesn’t impact parish liturgy. People who are skilled (more or less) at reading in public proclaim the Scriptures. People who are devoted (more or less) distribute the Eucharist. It’s not terribly different from the situatio with clergy, who as a group, are more or less competent in presiding, preaching, and other liturgical tasks.
What the Church describes as an acolyte is a blending of three roles in most parishes: sacristan, altar server, and Communion minister:
98. The acolyte is instituted for service at the altar and to assist the Priest and Deacon. It is his place principally to prepare the altar and the sacred vessels and, if necessary, to distribute the Eucharist to the faithful as an extraordinary minister.[cf. Canon Law 910 §2; Ecclesiae de mysterio (1997) 8]
In the ministry of the altar, the acolyte has his own proper functions (cf. nos. 187-193), which he must carry out in person.
The lector functions largely as envisioned here:
99. The lector is instituted to proclaim the readings from Sacred Scripture, with the exception of the Gospel. He may also announce the intentions for the Universal Prayer and, in the absence of a psalmist, recite the Psalm between the readings.
In the celebration of the Eucharist, the lector has his own proper function (cf. nos. 194-198), which he himself must carry out.
Most often in American parishes, men, women, youth, and children serve in these roles:
100. In the absence of an instituted acolyte, there may be deputed lay ministers to serve at the altar and assist the Priest and the Deacon; these carry the cross, the candles, the thurible, the bread, the wine, and the water, or who are even deputed to distribute Holy Communion as extraordinary ministers.[cf. Immensae caritatis 1; Canon Law 230 §3]
101. In the absence of an instituted lector, other lay people may be deputed to proclaim the readings from Sacred Scripture, people who are truly suited to carrying out this function and carefully prepared, so that by their hearing the readings from the sacred texts the faithful may conceive in their hearts a sweet and living affection for Sacred Scripture.[cf. Sacrosanctum Concilium 24]
My own sense is that the American way works better than the institution route. People are discerned with gifts. These gifts are cultivated in the context of a living faith community and are not part of a hierarchy. I suppose a case might be made otherwise, but I have yet to hear a convincing one.