Yes I know there have been discussions about this topic many a time in the past. I would be in line next to you when it comes to saying that Riba is explicitly haram in Islam.
I myself researched both conventional and Islamic alternatives available to me before I had taken a home mortgage a couple of years ago and I indulged in a conventional loan knowingly that it is a sin and I always ask forgiveness for it but my circumstances warranted the need for a house for I have parents and family under my responsibility to house, not an easy task in USA. I do not advocate interest based banking either but needs differ from person to person based on circumstances.
It appears that your concern about Islamic alternatives is the same as what I had concluded back then and still now, they are vicious and devoid of the charitable purpose of a loan in Islam. As I mentioned earlier in one of my posts, they do not provide social justice in transaction, which is part and parcel of the reasons for forbidding Riba to establish justice and equality in trade and transaction not exploit.
Yet it remains that all early jurists have allowed a portion of the price for time deferrment of payment. The question remains and there is not concensus from what I have researched thus far, when does this markup become exploitive enough to deviate from the very evil it is supposed to save us from.