I'm not sure where to start, so bear with me if my response seems a bit disjointed.
First of all, let's consider the city's intent in its RFP. A significant weighting is given to housing outcomes and affordability (including diversity of housing form and number of bedrooms), overall housing supply/maximizing density, and alignment with the municipal plan (including the affordable housing strategy). So we can surmise that the city wants a bunch of housing on this site, including some geared towards lower incomes and to families.
The RFP also says that it needs to do this while being "sensitive to the built context of the surrounding neighbourhood". The site is surrounded by approximately 35 low-rise residential structures, ranging from single family homes to small apartment buildings. I'm not familiar with Saint John's municipal plans but in Fredericton that context would likely limit you to four storeys for most of the site, because the municipal plans calls for appropriate transitions from adjacent low rise housing. What makes things complicated for this site is that the low rise housing existing around most of the perimeter of the site. If it was just along one side such a transition would be a lot easier. You said that neighbours would be against this regardless of height, and while that is no doubt true, it's certainly more impactful to have a 10-storey building next door than it is to have a 3-storey building, especially when there is no existing precedent for such height in the area.
Regardless of that, even if building taller was appropriate in the context of the neighbourhood, there are issues with that as well. First of all, we've known for 50 years that the
towers in the park style of development doesn't work, and that's effectively what you're proposing here (and in the past you've proposed that for others sites as well). Density for the sake of density doesn't work well when the site offers very few amenities. People are willing to live in high-rises when have amenities nearby but this site offers nothing but your beloved ocean views.
Building taller is also ultimately more expensive, especially if you also want to incorporate underground parking – that increases the cost to build significantly. The other challenge is that it is much more difficult to delivery a significant number of family-size (3+ bedroom) units this way. Our building codes do not give a lot of flexibility in how those kind of layouts are designed.
You've cited building taller as a way to conserve the existing green space but you haven't articulated why that is desirable, or how that green space would be activated. We tend to overestimate the value of urban green space, particularly unmaintained space. I would argue that the value of a thoughtfully designed one acre park is much higher than 10 contiguous acres of mostly unmaintained grass and trees. And again, this is an area that is not lacking in green space to begin with.
So given the context of the site and how the RFP is written, what is being proposed seems appropriate for the site. The stacked townhouse form allows for a cost-effective way to deliver a mix of unit sizes (smaller single storey on the bottom, larger two storey on top). The project is easily phased and new homes can be delivered much more quickly than building mid or high rise buildings.
At the same time, I agree that this is a completely unambitious project, and I would place the blame for that on the city. The opportunities to provide significant residential developments on city-owned land generally don't come along often, and the goals for such developments should be to deliver a housing product to an underserved market – that generally means some combination of price point and housing topology.
Rather than putting out a fairly open-ended RFP the city could have created a master plan for the entire property and then subdivided lots off of it that could be sold to developers with pre-approved development plans in place. As adamuptownsj mentioned in the other thread, there's definitely an opportunity for mid-rise buildings along the Lowell Street frontage. A small, fully activated, centrally located park could be built somewhere in the middle of the property, alongside the trail that is in the current proposal. That could have been surrounded by stacked townhouses (rentals) and perhaps row houses (owner occupied).
There could still be an affordable component to this plan by partnering with perhaps the province, nonprofit community groups, creating a co-op building, etc. That would have resulted in a lot more diversity in terms of housing topologies, incomes, etc. You could have even reserved a lot along Lowell for a mixed-used building as a final phase of the project in case the population growth of the area supports that.
Such a project could be a catalyst for the entire neighborhood, spurring development of the land on the other side of Woodville. I'm sure there are other opportunities for gently density redevelopments in that area as well.
I would just add that regardless of how such a project is funded, there needs to be an emphasis on affordability, and delivering that in a cost effective manner. You're effectively advocating for a luxury product on city-owned land and I don't think that is fair to taxpayers. We can have high quality yet relatively modest housing instead that fits a real need in the community. Your point about being happier in a high-rise building with ocean views than in a stacked townhouse is moot if you can't afford the high-rise, or if that form factor doesn't work for you and your family.