The average telmisartan dose in monotherapy (73.5 mg) decreases SBP by 13.5 mm Hg and DBP by 8.7 mmHg per Treatment efficacy of anti-hypertensive drugs in monotherapy or combination. But you could take the lowest dose (20 mg) and get a lower reduction (that I estimated at about -10/-7, as it’s nonlinear). So with 120-130/70-80 and 20 mg telmisartan you might be fine. However, antihypertensive drugs show massive differences between individuals. For instance, the same paper says:
When the characteristics of the patients showing the overall best antihypertensive response were assessed, the associated variables were female sex, higher BMI, and Caucasian ethnicity, whereas Afro-American ethnicity and normal weight were associated with a lower response to antihypertensive drugs. Women experienced better antihypertensive response overall, and specifically to thiazides, ARBs, and combinations. Agarwal et al[5] also showed that women had better antihypertensive response to combinations (both, CCBs plus olmesartan and thiazide diuretics plus olmesartan) than men.
And your daily pattern matters as well. You don’t want to be in hypotension. Doing a 24h BP monitor might help to make the best decision. Telmisartan seems to be able to “smooth” your BP variability no matter your pattern, which, if true, would be a great thing: Effect of telmisartan vs. ramipril on ‘dipping’ status and blood pressure variability: pooled analysis of the PRISMA studies
Coming back to the OP’s question, most hypertension guidelines say that “antihypertensive medication should start with SPCs to ensure more rapid, effective BP-lowering” (source). SPC means “single pill combination” such as telmisartan/amlodipine. For instance, the 2023 European guidelines say: “Initiation of therapy with a two-drug combination is recommended for most hypertensive patients. Preferred combinations should comprise a RAS blocker (either an ACE inhibitor or an ARB) with a CCB or Thiazide/Thiazide-like diuretic. Other combinations of the five major drug classes can be used.”
So could you combine telmisartan and rilmenidine? I can’t find data on this…
Sartans are indeed interesting (see, for instance Candesartan inhibits Toll-like receptor expression and activity both in vitro and in vivo) but candesartan failed in the ITP. However, do mice die of hypertension? I don’t know 
It’s also interesting that despite the failure of candesartan, the ITP team decided to test another sartan: telmisartan (this time in combination with a statin). There’s a lot of positive longitudinal data on ARBs (see the related topic: Angiotensin II receptor blocker (ARB) experiences? - #8 by adssx ) and they seem safe. On the other hand, we just have one recent paper showing that rilmenidine extends lifespan in worms. This paper has only been cited 9 times so far. And there are two clinical trials ever registered!
(That being said, friends of mine recently looked at repurposing candidates for Alzheimer’s and they identified Debrisoquine, Guanethidine, Minoxidil, Doxazosin, Hydralazine, Sitaxentan, Pargyline, Reserpine, Bosentan, and Deserpidine as top candidates. Surprisingly, all these drugs belong to the same ATC category as rilmenidine… Generating new drug repurposing hypotheses using disease-specific hypergraphs)
