1) Local church only. In this model there is no place for the para-church. Here each local church is responsible for their own ministry & outreach to students. Perhaps this would be closest to the article previously quoted from CSM in the UK. http://www.churchstudentministries.org/
The advantages of this model are obvious.
a) There is no confusion of responsibilities - it all falls under the authority & teaching of a local church... at least on paper. No difficult relationship between local church and parachurch need be navigated. There is just the local church.
b) This in turn means that the danger of placing unnecessary burdens upon immature Christians is all but eliminated, or at least overseen in exactly the same way as leadership in any other ministry of the local church. There is no necessity for student leadership in this model at all, but there is also the possibility of student leadership with appropriate oversight, if that be deemed wise by the local church.
c) The local church is clearly affirmed and edified by this model.
d) It appears more biblical, because we don't clearly see parachurch organisations in the bible (for arguments to the contrary see http://www.uccf.org.uk/resources/articles/Ecclesiology.pdf pp 16-19)
a) The very nature of the interconnected relationships within a campus of Christians in different churches means that it is natural and commendable that people will have Christ-Centred relationships with their brothers & sisters who attend different local churches.
b) Should they never work together in gospel partnership with those brothers and sisters? should they not ever put on evangelistic events? Should they not, for example hold an evangelistic bible study in one of their rooms on Campus that members of First Baptist, Second Presbyterian & St. Someone's Anglican & Covenant Grace reformed charistmatic church all invite friends to because they all live in the same building. This would have several obvious benefits.Might not this gospel partnership aid the witness to the gospel, as the Non-Christian gets to see that evangelical Anglicans, Charismatics, Presbyterians & Baptists are all holding out to them the Same gospel. What if this sort of thing takes off around the University. Would it be wrong for them to get together to pray for one another & share ideas? Should they not draw up some sort of doctrinal basis & even constitution to make it clear who it would be wise to be in gospel partnership with and who it wouldn't? But then you have a parachurch, and the relationship between the parachurch and the local church once again needs to be navigated.
c) If I as a pastor of one local church get to know students who are members of another local church I am not going to refuse to have a relationship with them just because they come from another local church. I will not refuse to speak into their lives. I will, therefore, to some extent disciple them (though, in regards to the local church, if they are attending another evangelical church, I will disciple them towards a more healthy involvement in their local church, not mine.) I don't think that this undermines their church, though it does raise exactly the same questions of accountibility etc. that are raised by an organised parachurch.
d) In the bible we also don't see several different churches from different denominations within a single city. The way in which such churches relate to each other must be negotiated & we can't expect clear precident from Scripture as to how this must be done.
So, in summary, on paper this model appears to avoid the pitfalls of trying to work out the relationship between church and parachurch. In reality it will create the same problems, but with the added danger of assuming that the problems don't exist. As long as this danger is not naively ignored, I am sure that this model could work well. Local churches will just need to give wise council to their students as to how to parnter informally with other Christians.