Rhinos...what roles do they fulfill in my army?

Hey guys I'm back again with some more strategic advice I have for newer players.

To be honest, Rhinos are very dull and straight forward vehicles. But you gotta give them some love though. Their cheap 35 point models and they get troops where they need to be, even though they're slow vehicles. They only have a storm bolter, and they can have an extra storm bolter or hk missile. But both options aren't really worth it because points are better spent elsewhere. So why are 4 of them in my list for anyways? Look at the footprint of a Rhino closely. They can give all the vehicles of an sm army (except drop pods) cover saves. They can take hits from incoming fire for bikers, marines, and terminators by blocking line of sight. Little things like this are very important things I take in consideration for my list ecspecially because all my models can get mobile cover with my Rhinos. I also need Rhinos for getting my magic multimeltas in range against other mech lists. But then people will say, but if you move the Rhinos, you're multimeltas can't shoot. Yes this is true, but I just need to move them a foot across the table, and that 24 in range can do something next turn. On top of that they're free, but then again there are missile launchers. If I want to take missile launchers though, I will spam them out in my whole army. I actually have a list with 21 missiles, and 76 marines in 2000 points. But in my current list I have 11 Multimeltas and I need mms in my troops to support my Dreads, and Speeders because my list is very synergetic. That's enough about multimeltas though, so let's continue with Rhinos. Alright so if I got my troops where they need to be, what can I do with the Rhinos now? That's simple, I can A) Tank shock troops off an objective or B)Use them to block LOS on my troops so they don't get shot up. The first choice is a suicidal move, but hey I have 4 of them and I don't care if I need to lose all of them to win because if they're cheap, they're expendable. Tank shocking isn't something  I seevery often but when the opportunity is there then why not? If I need to provide a target my opponent needs to get rid of instead of my troops, then it's worth the trade. In the picture above if you look at all the marines on the back of the table, it's because the Rhinos got them away from the objective in the crater (under the baby blue rhino). In choice B, I used the baby blue rhino to land on top of the objective on turn 4 so, my marines can't be shot up. So my opponent has to shoot it up, to claim the objective however Rhinos aren't hard to kill. At least the marines, are saved from the shots on the rhino though so it evens out. Another choice that is available is what is called speedbumping, which is to move a unit up the table to intercept an enemy unit through combat. But you can do this with rhinos even if they are vehicles. Just move 12 in up towards an enemy unit to prevent assault and pop smoke if needed. That way, the enemy unit needs to shoot or assault it. If they destroy it, it doesn't matter because now the unit needs to go through difficult, or dangerous terrain to get to my forces. Of course bikes, calvalry, or jump packers can go around it so it is a down side. But the idea is to speedbump the unit, so you can shoot at it as it moves slowly up the table. So all in all, you have a cheap unit to use to gain the upper hand tactically. Other transports like Landraiders, Monoliths, Wave serpents, etc. can do all of the things Rhinos can do. However the rhino has an advantage, it's cheap and expendable. All those other vehicles aren't easily spammed out like rhinos, so that's an important thing to remember over the other vehicles with the troops in a pimped out ride and bells and whistles. Thus rhinos are perfect for MSU SM armies and are worth considering. There's some food for thought to chew on.