If memory serves me correctly, Paul does encourage the faithful to actively seek the gifts of the Holy Spirit, including speaking in tongues and prophecy. I believe you’ll find the pertinent passages in 1 Corinthians somewhere. But Paul also emphasizes that these gifts have their proper place and function. And of course Paul encourages that we all strive after the gift of love above all things, because all other gifts will cease when we “no longer see dimly, as in a mirror, but face to face.” In the Charismatic events that I’ve been to this order has almost always been maintained. The “extraordinary” gifts of prophecy and tongues are encouraged, but love - both of God and of neighbor - is encouraged above all things.
No, the saints did not boast of their gifts, and often tried to hide them out of humility. But not all charismatics boast of these gifts either, and many do indeed try to hide them. I know some who only pray in tongues during their private prayer time and out of the earshot of others.
As to whether or not the people in the Renewal do the same thing as the Apostles on Pentecost, or that St. Paul encouraged, biblical scholars say that yes indeed, this is one possible interpretation of what happened at Pentecost and in the early Church.
Of course all gifts can be misused. The gift of free will is the most frequently misused, followed, of course, by the gift of reason. But just because a gift is misused does not de facto make the gift (or the Giver by implication) bad or any less a true gift.
The way we know whether or not any movement within the Church is using its gifts and/or its charism (role within the Church) properly is by trusting in the competent authorities to pass judgment. As has been pointed out time and again in this thread, the past several Popes have all been supporters of the Renewal. John Paul II is often said to have been a member of the Renewal, although you’ll not find that in writing. It also seems that the large majority of bishops in the Church are also supporters of the Renewal, as there are active groups in nearly ever diocese, at least here in the States.
As to whether or not members of the Renewal practice fasting, prayer, etc., I can affirm that with a resounding “yes.” Often times they are the most enthusiastic, voluntarily fasting on Fridays when the Church at large seems to have abandoned this practice, some even fast on Wednesdays as well. Many that I’ve known faithfully pray Morning and Evening Prayer from the Liturgy of the Hours, attend daily Mass, and go to Confession on a regular basis! Many attend regular prayer meetings, where they gather with their brothers and sisters in Christ outside of a liturgical context to offer prayers of praise, adoration and thanksgiving to our God Who has bestowed so many great blessings upon us.